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Program Detail
& Abstract Booklet
Organized By
Department of Chemistry & Biochemistry
Dallas-Fort Worth Section of the American Chemical Society
50
th Annual Meeting-in-Miniature
Saturday, April 29, 2017
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU
Important information
The meeting will be held on Saturday, 29th April 2017 in TCU's Sid W.
Richardson Physical Sciences Building (http://www.maps.tcu.edu/)
You can park in any white-lined space on campus. The lots across the street
from Sid W. Richardson Physical Sciences Building and the Lot 15 on W.
Lowdin St. between Lubbock and Merida Avenues are recommended
(http://www.maps.tcu.edu/)
Presenters must copy their presentation to the computer available in each
session room. Please arrive early to have your presentation loaded into the
computer from your flash drive/disc and to address any technical
difficulties
All session rooms will have Screen, Projector, VGA, HDMI Cables (If you want
to use your own Laptop)
Be aware of your time as you will be held to the time allotted. Allow 3-5
minutes for questions from audience which must be included in your total
time allotment. You may also make yourself available to answer questions
after the session
If you are unable to present on your scheduled day/time, notify by email at
[email protected] or at [email protected]
Prepared By Arshad Mehmood Graduate Student Computational Chemistry, TCU.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU
Table of Contents
Schedule At-A-Glance 01
Section 1
Undergraduate 1 02
Undergraduate 2 10
Undergraduate 3 17
Section 2
Inorganic/Materials Chemistry 1A 24
Inorganic/Materials Chemistry 2A 32
Inorganic/Materials Chemistry 3A 39
Section 3
Inorganic/Materials Chemistry 1B 45
Inorganic/Materials Chemistry 2B 53
Inorganic/Materials Chemistry 3B 60
Section 4
Organic/Analytical Chemistry 1 66
Organic/Analytical Chemistry 2 74
Organic/Analytical Chemistry 3 81
Section 5
Organic/Biochemistry 1 88
Organic/Biochemistry 2 96
Organic/Biochemistry 3 103
Section 6
Physical/Computational Chemistry 1 111
Physical/Computational Chemistry 2 119
Physical/Computational Chemistry 3 126
Presenters Index 133
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature
Schedule At-A-Glance
Section 1 2 3 4 5 6
Venue LH* 1 LH 3 LH 2 LH 4 SWR 446 SWR 360
Category Undergraduate
1
Inorganic/ Materials
1A
Inorganic/ Materials
1B
Organic/ Analytical 1
Organic/ Biochem.
1
Physical/ Computational
1
08:45-09:00 Patel Ren Brown McCabe Miller Niedbalski
09:00-09:15 Orr Oswald Melancon Pathiranage Davis Najafian
09:15-09:30 Barrera Mayberry Ponduru Asgari J. Cao Montelongo
09:30-09:45 Nance Yaseen Kamras Chinthala Noonikara Wang
09:45-10:00 Barnett Wilk Sotelo Hu Ojo Jones
10:00-10:15 Ravi Lin Ivy Yellappa Nagar Parveen
10:15-10:30 Zometa Vizuet Jayathilaka Barragan Mudasiru Parish
Break
Undergraduate 2
Inorganic/ Materials
2A
Inorganic/ Materials
2B
Organic/ Analytical 2
Organic/ Biochem.
2
Physical/ Computational
2
11:00-11:15 Young Y. Cao Korir Mammoottil Aljowni Wang
11:15-11:30 Schostag Harris Johnston Avullala Alahakoon Nazemi
11:30-11:45 Reeves Brewer Almotawa Budy Dakarapu Medel
11:45-12:00 Samuel Palacios Buford Gayan Seal II Lyu
12:00-12:15 Villegas Perera Williams Shao Chunduru Sun
12:15-12:30 Howlett Benton MacKenzie Ryan Green Oliveira
Lunch
Undergraduate 3
Inorganic/ Materials
3A
Inorganic/ Materials
1B
Organic/ Analytical 3
Organic/ Biochem.
3
Physical/ Computational
3
01:30-01:45 Agbo Otten Shennara Singh Ochoa Tao
01:45-02:00 Martin Vaish Omer Herath Bunton Ranathunga
02:00-02:15 Burge Farvid D’Achille Thapa Kale Zhou
02:15-02:30 Quimbar Benavides Sardar H. Nguyen Castillo Kim
02:30-02:45 Foley D. Nguyen Kumar Gobeze Obondi Shen
02:45-03:00 Weber - - Bokka Montoya Humason
03:00-03:15 - - - - Sharma -
03:15-03:45 Judging
03:30-04:15 Tours
04:15-05:00 Awards-LH 1 *Sid W. Richardson Physical Sciences Building: Lecture Hall
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 2
Section 1
Undergraduate 1 Sid W. Richardson Physical Sciences Building: Lecture Hall 1
Time Presenter Title
08:45-09:00 Shreya Patel Southern Methodist University
A Volumetric Three-Dimensional Digital Light Photoactivatable Dye Display
09:00-09:15 Melissa Orr University of Texas at Arlington
Synthesis of Inorganic Pigment ALn2S4 (A= Ca, Sr, Ba; Ln= La, Ce, Pr)
09:15-09:30 Maribel Barrera University of North Texas
Solubility of sorbic acid in organic mono-solvents: calculation of Abraham model solute descriptors from measured solubility data
09:30-09:45 Patricia Nance Southern Methodist University
Synthesis and Characterization of Antibacterial Polyphosphazene Materials
09:45-10:00 Maddie M. Barnett Texas Christian University
Determining the antioxidant activity of small metal-binding ligands that target agents known to lead to neurodegenerative diseases
10:00-10:15 Sanjana Ravi University of Texas at Dallas
Synthesis of Silica Centipede Nanoparticles for Drug Delivery Purposes
10:15-10:30 Diego F. Zometa Abilene Christian University
The first molecular square containing eight osmium atoms
Undergraduate 1 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 3
A Volumetric Three-Dimensional Digital Light Photoactivatable Dye Display
Shreya Patel, Jian Cao, Alexander R. Lippert*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Undergraduate
Division: Organic Chemistry
Three dimensional (3D) displays have captivated the minds of many, and with science fiction movies like
Star Wars, Iron Man, and Avatar, 3D displays have become synonymous with the future of imaging
technology. Aside from the entertainment industry, 3D displays could have significant applications in
medical, architectural, mathematical, and even chemical modeling as visualization tools. Due to complex
fabrication requirements, it is incredibly difficult to generate 3D images, and so 3D imaging techniques
are not currently commonplace. We report a new technique of volumetric 3D imaging, the 3D digital
light photoactivatable dye display (3D Light PAD). The 3D Light PAD relies on a small photoswitching
molecules that fluoresce at the intersection of visible light and UV light. By manipulating beams of light
using a commercial picoprojector and a projector fitted with a UV LED, we have been able to generate
3D images and animations with a minimum voxel size of 0.68 mm3, 200 µm resolution, and stability over
an extended amount of time. This technique of imaging is easy to operate and relatively inexpensive. The
synthesis, characterization, and the technique of the 3D Light PAD will be presented.
Undergraduate 1 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 4
Synthesis of Inorganic Pigment ALn2S4 (A= Ca, Sr, Ba; Ln= La, Ce, Pr)
Melissa Orr, Adriana Paolo Sotelo, Dr. Robin T. Macaluso*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Undergraduate
Division: Solid State/Inorganic Chemistry
Current inorganic pigments raise real world issues such as the cost and danger of synthesis, toxicity,
and environmental safety. Additionally, recent federal regulatory legislation has sparked interest in the
importance of finding new non-toxic high-performance pigments to be used in plastics, paints, and
ceramics, especially in the red color range. A few rare-earth sulfides have been used for this purpose,
however, their synthesis presents challenges for large scale implementation. This work examines ALn2S4
(A= Ca, Sr, Ba; Ln= La, Ce, Pr) as promising pigment materials and presents a novel synthesis route
which eliminates the flow of toxic and corrosive gases and complex heating processes.
Undergraduate 1 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 5
Solubility of sorbic acid in organic mono-solvents: calculation of Abraham model solute descriptors from measured solubility data
Maribel Barrera, William E. Acree*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Undergraduate
Division: Analytical Chemistry
Experimental mole fraction solubilities are reported for sorbic acid dissolved in methanol, ethanol, 1-
propanol, 1-butanol, 1-pentanol, 1-hexanol, 2-propanol, 2-methyl-2-propanol, 2-pentanol, diisopropyl
ether, methyl tert-butyl ether, tetrahydrofuran and 1,4-dioxane at 298.15 K. Results of the experimental
measurements, combined with a published water-to-octanol partition coefficient and published solubility
data for sorbic dissolved in acetone, ethyl acetate and acetonitrile, were used to calculate Abraham
model solute descriptors for the sorbic acid monomer. The calculated solute descriptors were found to
describe the measured solubility and partition coefficient data to within 0.10 log units. The calculated
solute descriptors can be used to predict sorbic acid solubilities at 298.15 K in additional organic
solvents in which sorbic acid is expected to exist predominately in monomeric form.
Undergraduate 1 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 6
Synthesis and Characterization of Antibacterial Polyphosphazene Materials
Patricia Nance, Patty Wisian-Neilson*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Undergraduate
Division: Inorganic Chemistry
Properties of the polyphosphazene, [RR'PN]n, can be selected for specific purposes by post
polymerization modification of the side groups, R and R', which are attached to the polymeric backbone
via phosphorus carbon bonds. Poly(methylphenylphosphazene) (PMPP) is among the most extensively
studied of these alkyl/aryl polyphosphazenes, which are synthesized by condensation polymerization of
N-silylphosphoranimines. PMPP is most easily modified by deprotonation of the methyl group followed by
substitution of electrophiles. This ongoing work explores the use of this method to substitute
antibacterial groups onto the polyphosphazene backbone so that they may be used as infection-
preventing films for biomedical applications. Thus far, two immediate precursors to antibacterial
polyphosphazenes have been synthesized and characterized, and the methodology for the final synthetic
step to each polymer is being developed. Additionally, experiments were performed to increase percent
substitution of the precursor groups to yield effective antibacterial group substitution levels.
Undergraduate 1 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 7
Determining the antioxidant activity of small metal-binding ligands that
target agents known to lead to neurodegenerative diseases
Maddie M. Barnett, Hannah. M. Johnston, Kayla N. Green*
Department of Chemistry and Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Undergraduate
Division: Inorganic Chemistry
Oxidative stress in the brain is a known contributor to the development of neurodegenerative diseases,
including Alzheimer’s. The focus of this project is to target the amyloid-β plaque formations and reactive
oxygen species (ROS) derived from mis-regulated metal-ions that lead to disease-causing oxidative
stress. The present investigation is measuring the antioxidant reactivity of the new molecule L4. L4
contains two radical scavenging pyridol groups along with a metal-binding nitrogen rich ligand system. It
was hypothesized that increasing the number of pyridol groups in our small molecule library would
increase the radical scavenging activity, which in turn may provide cells protection from oxidative
stress. The radical scavenging ability of L4 was quantified using the 2,2-diphenyl-1-picrylhydrazyl (DPPH)
radical assay and this was compared to other radical scavenging small molecules to evaluate the effect
of the additional radical scavenging group on the antioxidant activity. The interaction of L4 with redox
active metal-ions such as copper(II) was also evaluated to show the molecule’s ability to target
misregulated metal-ions in diseased tissues.
Undergraduate 1 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 8
Synthesis of Silica Centipede Nanoparticles for Drug Delivery Purposes
Sanjana Ravi, Jason Lin, Kenneth Balkus Jr.*
Department of Chemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Undergraduate
Division: Inorganic Chemistry
Today, most cancer patients are treated with nonspecific antitumor drugs that are distributed
throughout the body following intravenous injections. These drugs attack both healthy and cancerous
tissue, causing a weakened immune system, among many other effects. By using a wrinkled silica coated
magnetic core, tumors can be directly targeted. While synthesizing wrinkled silica, silica structures,
named centipedes were observed. These centipedes contain a smooth surface with legs protruding from
the surface. Since the centipede has a width of 30 nm, the centipede can fit inside the pores of tumorous
tissues and deliver chemotherapy drugs. This, along with its chemical and thermal stability makes it
optimal for drug delivery purposes.
The current synthesis for these centipedes is by using urea, cetylpyridinium bromide, water, cyclohexane
and tetraethyl orthosilicate. Since centipedes have not been published, the correct environment under
which only centipedes form is still being discovered. Currently, we are bubbling carbon dioxide into the
cetylpyridinium bromide in order to change the structure and pH of the surfactant, leading to a slightly
different template and hopefully creating these centipede structures. After solidifying the conditions, we
can coat magnetic cores with these centipedes to target tumors and make cancer treatment more
effective.
Undergraduate 1 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 9
The first molecular square containing eight osmium atoms
Diego F. Zometa, Dr. Gregory L. Powell*
Department of Chemistry and Biochemistry, Abilene Christian University
E-mail: [email protected]
Category: Undergraduate
Division: Inorganic Chemistry
Based on the ability of ruthenium carbonyl to combine with dicarboxylate anions to form triangular and
square macrocycles consisting of dimetal sawhorse units, we have been investigating reactions of
osmium carbonyl with dicarboxylic acids. Significantly higher temperatures are required to activate the
Os–C bonds in osmium carbonyl compared to the Ru–C bonds in ruthenium carbonyl, but with the use
of a microwave heating, one triangular hexanuclear osmium sawhorse complex was recently prepared
in our lab. We decided to attempt the syntheses of additional macrocyclic complexes by reacting
Os3(CO)12 with 1,3-adamantanedicarboxylic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid in
a microwave reactor. The X-ray crystal structures of three different products from these reactions will
be presented. The product with 2,6-naphthalenedicarboxylate ligands is the first example of a molecular
square with eight osmium atoms. The other products include a tetranuclear molecular loop and a
hexanuclear molecular triangle.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 10
Section 1
Undergraduate 2 Sid W. Richardson Physical Sciences Building: Lecture Hall 1
Time Presenter Title
11:00 -11:15 Mackenzie Young Southern Methodist University
Synthesis and Characterization of Polyphosphazenes with Pyridine Substituents
11:15-11:30 Kelly Schostag Southern Methodist University
A Novel Synthesis of Thiols Under Mild Conditions
11:30-11:45 Audrey Reeves Southern Methodist University
Imaging Acetaldehyde Formation During Ethanol Metabolism in A549 Cells using a Hydrazinyl Naphthalimide Fluorescent Probe
11:45-12:00 Anthony B. Samuel University of Texas at Dallas
Determining the structural stability of single crystalline Ln3Co2Sn7 (Ln = La-Nd, Sm, Gd)
12:00-12:15 Hector Villegas Texas Christian University
Intramolecular nonbonded attractive interactions
12:15-12:30 Thomas Howlett University of Texas at Dallas
Synthesis of Holmium Iron Garnet Nanoparticles coated with wrinkle silica and periodic mesoporous organoslica for Cancer Treatment
Undergraduate 2 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 11
Synthesis and Characterization of Polyphosphazenes with Pyridine Substituents
Mackenzie Young, Patty Wisian-Neilson*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Undergraduate
Division: Inorganic Chemistry
Polyphosphazenes, [RR'PN]n, are inorganic polymers with a broad range of properties largely determined
by the nature of the groups R and R' attached to the phosphorus in the PN backbone.
Poly(alkyl/arylphosphazenes) are prepared by thermolyis of Si-N-P compounds which contain simple alkyl
and aryl P–C bonded groups. The simplest and best studied of these is poly(methylphenylphosphazene),
PMPP, 1, where the methyl group is readily modified by deprotonation-substitution reactions. The
intermediate polymer anion, 2, formed by deprotonation reacts with several types of electrophiles
allowing for incorporation of new functionality and subsequent alteration of properties of the polymeric
materials. In this study, the electrophile pyridine carboxaldehyde was used to attach pyridine groups
which offer both metal coordination sites and potential bioactivity to the polymer system. The synthetic
conditions, characterization by NMR spectroscopy, and potential applications of this new polymer
system will be discussed.
n-BuLi
n
P N
Ph
CH3
yx
P N
Ph
CH2
P N
Ph
CH3Li+
_
N C
O
H
P N
Ph
CH3
P N
Ph
CH2
C OHH
N
x y
..
1 2 3
Undergraduate 2 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 12
A Novel Synthesis of Thiols Under Mild Conditions
Kelly Schostag, David Son*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Undergraduate
Division: Organic Chemistry
Thiols have shown great usefulness in many fields for a variety of purposes including being used as
stabilization agents, in synthesizing other compounds, and as protective coatings. Unfortunately, thiols
have limited commercial availability due to the harsh conditions under which they are synthesized. Past
research in the Son Lab has shown that some thiols can be synthesized with high yields under milder
conditions by reacting a trithiocarbonate sodium salt with a brominated compound. Here we study these
methods of thiol synthesis in order to verify the past results and expand the number of thiols synthesized
with these procedures. There are two methods used in the past study: one uses heat to accelerate the
reaction, and the other uses a phase transfer catalyst. In our report we focus on the latter method. We
confirmed this method can be used to synthesize thiols, but at nowhere near a commercial level quantity.
In the future, we will continue to study this method using different phase transfer catalysts, and expand
our study to include other halogenated compounds as starting materials.
Undergraduate 2 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 13
Imaging Acetaldehyde Formation During Ethanol Metabolism in A549 Cells using a Hydrazinyl Naphthalimide Fluorescent Probe
Audrey Reeves, Alexander Lippert*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Undergraduate
Division: Chemical Biology
Acetaldehyde plays a notorious role as a toxic intermediate in the enzymatic metabolism of ethanol. The
undesired side effects of this metabolism – headache, nausea, dry mouth, vertigo, and sensitivity to light
and sound – mark the well-known symptoms of a hangover. However, due to the challenges associated
with the study of small molecules in living cell metabolism, the precise biochemical events that lead to
these pathologies remain unclear. Here, we have visualized the metabolism of ethanol to acetaldehyde
in living lung epithelial cells using a hydrazinyl naphthalimide fluorescent probe. Utilizing a condensation
reaction between carbonyls and a hydrazine moiety, we demonstrate that the fluorescent probe AF1
reacts with a range of reactive carbonyl species including formaldehyde, acetaldehyde, glyoxylic acid, and
methyl glyoxal. We have applied AF1 towards the visualization of acetaldehyde generated from alcohol
dehydrogenase mediated ethanol metabolism, validating it as a useful tool to study the roles of alcohol
in respiratory disease and other pathological mechanisms.
Undergraduate 2 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 14
Determining the structural stability of single crystalline Ln3Co2Sn7 (Ln =
La-Nd, Sm, Gd)
Anthony B. Samuel, Thomas J. Martin, Julia Y. Chan*
Department of Chemistry, The University of Texas at Dallas,
E-mail: [email protected]
Category: Undergraduate
Division: Inorganic Chemistry
As part of our study to determine the structural stability of stannide intermetallics, we report the
synthesis, crystal growth and characterization of Ln3Co2Sn7 (Ln = La-Nd, Sm, Gd). By taking advantage of
a eutectic point of the lanthanide and cobalt, we are able to synthesize the desired phase at
temperatures lower than the reactants’ melting point. We first arc-melt the constituents, then grind the
product into a fine powder prior to characterization of our sample by X-ray diffraction. In this
presentation, I will present the structural details and discuss future work in our effort to grow single
crystals of the Ln3Co2Sn7 phase.
Undergraduate 2 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 15
Intramolecular nonbonded attractive interactions
Hector Villegas, Benjamin G. Janesko*
Department of Chemistry & Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Undergraduate
Division: Physical/Computational Chemistry
While cis/Z-substituted alkenes are usually less stable than their trans/E-substituted counterparts, the
cis-2-butenyl anion shows a higher preference over the trans-isomer. Calculations suggest that the
discrepancy is due to two cooperating effects: electrostatic interactions between the anionic center (C1)
to the methyl group (C4) and coupling between the C=C pi* antibonding orbital and both the CH2 pz and
CH3 C-H sigma bonds. Supporting the charge transfer is the fact that substitution on C1 with EDG
stabilizes the cis more while substitution on C4 with EWG stabilizes the cis more. For the coupling
interaction the C=C bond was stretched which increased the cis stabilization by lowering the pi* orbital
energy and increasing the coupling between the lone pair on C1 and pi*.
Undergraduate 2 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 16
Synthesis of Holmium Iron Garnet Nanoparticles coated with wrinkle silica and periodic mesoporous organoslica for Cancer Treatment
Thomas Howlett, Jason Lin, Kenneth Balkus Jr.*
Department of Chemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Undergraduate
Division: Inorganic Chemistry
The Holmium Iron Garnet (HoIG) nanoparticle has shown to be an effective delivery system for
chemotherapy while also being a source of radiation to eliminate cancer cells in a tumor. An exciting
addition to this is using Periodic mesoporous organosilica (PMO) to coat HoIG for more efficient drug
delivery. An important aspect of the PMO is that the surface area and functional groups can be changed
to work with hydrophobic and hydrophilic drugs. This can be expanded on by using a wrinkle silica
structure to improve overall surface area. The method for both the PMO and the wrinkle silica is to coat
a thin template layer of silica on the HoIG using TEOS. Then coat the surfactant, CPB or CTAB, to act as
the template for the next coating of silica to make a wrinkle structure. The final step for the PMO
synthesis is to add a mixture of benzylsilane and TEOS to achieve a wrinkled PMO structure. So far this
method has been successful in coating although loading and unloading has not been tested yet. The
future steps in this would be to shrink the particle size overall and continue to improve the coating
method.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 17
Section 1
Undergraduate 3 Sid W. Richardson Physical Sciences Building: Lecture Hall 1
Time Presenter Title
01:30 -01:45 Christiana Agbo Tarrant County College South Campus
Determination of alcohol content in beverages using nuclear magnetic resonance spectroscopy
01:45-02:00 Misty S. Martin University of Texas at Arlington
Matrix-assisted laser desorption/ionization time-of-flight – mass spectrometry for the characterization of groundwater microbiomes
02:00-02:15 Joshua Burge Tarrant County College South Campus
Characterization of fatty acid compositions of monovarietal olive oils from the Kalamata, Tuscan, and Sicilian regions using NMR Spectroscopy and Gas Chromatography
02:15-02:30 Miguel E. Quimbar Southern Methodist University
A chemiluminescent platform for smartphone monitoring of H2O2 in human exhaled breath condensates
02:30-02:45 Brandon J. Foley Southern Methodist University
Botrytis Cinerea Vivid Wild-Type and Mutant LOV Protein Photocycle Kinetics
02:45-03:00 Samuel Weber Southern Methodist University
Optogenetic System to Interrogate the Fungal Circadian Clock
Undergraduate 3 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 18
Determination of alcohol content in beverages using nuclear magnetic resonance spectroscopy
Christiana Agbo, Olga Papadopoulou, Martha Gilchrist*
Department of Natural Science, Tarrant County College South Campus
E-mail: [email protected]
Category: Undergraduate
Division: Analytical Chemistry
Ethanol, produced by fermentation of sugars, is the principal alcoholic component in alcoholic beverages
with concentrations ranging from 3% in beer to 50% v/v in spirits. Gas Chromatography (GC), fractional
distillation and spectrophotometry are analytical methods often used to quantify alcohol in beverages.
We have utilized the Magritek 43 MHz 1H-NMR spectrometer to determine the alcohol content in
beverages using the method published by Isaac-Lam et al. (Isaac-Lam, M. 2016). A calibration curve
was constructed and acetonitrile was used as an internal standard. Beverages including beer, wine, and
distilled liquor were analyzed and our data are in agreement with the manufacturer’s label.
Undergraduate 3 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 19
Matrix-assisted laser desorption/ionization time-of-flight – mass spectrometry for the characterization of groundwater microbiomes
Misty S. Martin1, Inês C. Santos1,3, Doug D. Carlton, Jr.1,3, Zacariah L. Hildenbrand2,3, Kevin A.
Schug1,3*
1Department of Chemistry and Biochemistry, University of Texas at Arlington.
2Inform Environmental, LLC, Dallas TX.
3Affiliate of the Collaborative Laboratories for Environmental Analysis and Remediation, University of
Texas at Arlington.
E-mail: [email protected]
Category: Undergraduate
Division: Analytical Chemistry
Groundwater is the main drinking water source in America. Hence, it is important to maintain its quality.
A major concern is the possible contamination of groundwater from unconventional oil and gas drilling.
Environmental stressors can contribute to the evolution of pathogenic microorganisms, which pose as
a health concern as groundwater provides a method of dissemination for antibiotic-resistant
microorganisms. Therefore, it is necessary to understand the impacts of contaminants on the
groundwater microbiome. Molecular techniques are used to characterize microbial ecology, but are
expensive and time-consuming. Matrix-assisted laser desorption/ionization (MALDI) time-of-flight –
mass spectrometry (TOF MS) is a significant alternative, because it is more rapid and cost-efficient. In
this work, the groundwater microbiome was assessed in contaminated groundwater using MALDI-TOF
MS. The bacteria were isolated using the membrane filter technique and cultured in selective media.
Identifications were confirmed through gene sequencing. Antibiotic susceptibility was determined.
Twenty-five bacteria were identified using MALDI-TOF MS. Of these, over 90% matched the sequencing
results. Overall, samples exhibiting the highest levels of contamination appeared to facilitate the growth
of pathogenic bacteria including, A. hydrophila, B. cereus, P. aeruginosa and S. maltophilia. These four
were resistant to most of the antibiotics tested.
Undergraduate 3 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 20
Characterization of fatty acid compositions of monovarietal olive oils
from the Kalamata, Tuscan, and Sicilian regions using NMR
Spectroscopy and Gas Chromatography
Joshua Burge, Pei Eng, Olga Papadopoulou, Martha Gilchrist*
Department of Natural Science, Tarrant County College South Campus
E-mail: [email protected]
Category: Undergraduate
Division: Analytical Chemistry
Olive oil has been cultivated in the Mediterranean since ancient times, and is a principal ingredient in the
Mediterranean diet. Recently, monovarietal olive oils have experienced increased consumer interest for
their distinctive flavor characteristics. In this study, gas chromatography and Nuclear Magnetic
Resonance spectroscopy are utilized to compare three monovarietal olive oils and to determine if these
methods can be used to differentiate between olive oils cultivated in these particular regions. GC analysis
indicates that the major fatty acids present in the three monovarietal EVOO’s are palmitic, oleic, and
linoleic. From our analysis, no statistical differences in their percent compositions are observed.
Preliminary NMR data suggest that one EVOO may be distinguishable based on aliphatic region
integration values.
Undergraduate 3 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 21
A chemiluminescent platform for smartphone monitoring of H2O2 in human exhaled breath condensates
Miguel E. Quimbar, Alexander R. Lippert*
Dedman College, Southern Methodist University
E-mail: [email protected]
Category: Undergraduate
Division: Analytical Chemistry
Noninvasive measurement of oxidative markers in clinical samples has the potential to rapidly provide
information for disease management, but is limited by the need for expensive analytical instrumentation
that precludes home monitoring or point-of-care applications. We have developed a simple to use
diagnostic platform for airway hydrogen peroxide (H2O2) that combines optimized reaction-based
chemiluminescent designs with an inexpensive home-built darkbox and readily available smartphone
cameras. Specialized photography software applications and analysis of pixel intensity enables
quantification of sample concentrations. Using this platform, sample H2O2 concentrations as low as 264
nM can be detected. The platform has been used to measure H2O2 in the exhaled breath condensates
of human subjects, showing good agreement with the standard Amplex Red assay.
Undergraduate 3 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 22
Botrytis Cinerea Vivid Wild-Type and Mutant LOV Protein Photocycle
Kinetics
Brandon J. Foley, Haley Stutts, and Brian D. Zoltowski*
Department of Chemistry, Center for Drug Discovery, Southern Methodist University
E-mail: [email protected]
Category: Undergraduate
Division: Analytical Chemistry
Blue-light photosensors are a type of LOV domain that sense light quantity and relay a signal to adapt to
constant levels or respond to changes in the environment. The signal transduction in response to light
stimuli involves protein:protein interactions that attenuate gene expression related to circadian clocks.
VVD is a specific type of LOV domain that was cloned into the Botrytis Cinerea fungal pathogen that
infects a variety of agricultural products. The pathogenicity of Botrytis Cinerea LOV proteins is blue light
and circadian clock dependent. In this study, we characterized Botrytis Cinerea VVD photocycle kinetics
with respect to base catalysis and temperature dependence for both wild-type protein and rate affecting
variants (T194I). Base catalysis with imidazole was found to accelerate the rate of recovery identically
for the T194I mutant and the wild-type protein. Eyring and Arhenius analyses indicated a single rate
limiting step in the thermal reversion with a moderate enthalpy of reaction and largely unfavorable
entropy of reaction for the T194I mutant.
Undergraduate 3 Sid. Richardson Lecture Hall 1
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 23
Optogenetic System to Interrogate the Fungal Circadian Clock
Samuel Weber, Brian Zoltowski*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Undergraduate
Division: Biochemistry
Organisms have developed circadian oscillators to allow adaptation to daily fluctuations in light-intensity,
metabolic resources and oxidative stress. The regulatory networks integrating these factors are
inherently complex, involving numerous components and multiple interconnected biological circuits.
Currently, analysis of such complex systems is limited to two general approaches. First, one can isolate
individual components and perform biochemical analysis to identify their functional role. Such an
approach affords keen insight into chemical regulation, but is limited in its ability to decipher how input
from multiple components is integrated on a systems-level. The alternative systems biology approach
incorporates networkwide analysis through mathematical modeling. The systems approach allows
insight into the global regulatory network, but is limited in its incorporation of fundamental chemistry.
Herein, we devise an alternative approach that allows interrogation of the entire network in the context
of the fundamental chemistry. Specifically, we devise an optogenetic system recapitulating the fungal
circadian clock. Through mutations that affect protein:protein interactions, light-regulated protein
allostery, and alteration of photochemical input we interrogate the integration of blue-light and oxidative
stress into the fungal circadian clock.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 24
Section 2
Inorganic/Materials Chemistry 1A Sid W. Richardson Physical Sciences Building: Lecture Hall 3
Time Presenter Title
08:45-09:00 Yixin Ren University of Texas at Dallas
Neodymium based Complexes bearing Phosphate Ligands for Living Ring Opening
Polymerization of ε-Caprolactone and D, L-
lactide
09:00-09:15 Iain W. H. Oswald University of Texas at Dallas
Resolving Crystallographic Disorder in Intermetallics Adopting the Yb3Rh4Sn13-Structure Type
09:15-09:30 Darrell D. Mayberry University of North Texas
Asymmetric Catalysis by Chiral Metal Clusters
09:30-09:45 Waleed Yaseen University of North Texas
Hydrophobic Fluorinated Polymers for Corrosion Protection on Aluminum Surface
09:45-10:00 Mikaela Wilk Texas Woman’s University
Synthesis and characterization of novel copper phenanthroline complexes: Tuning the structure and photophisics via alteration of the synthetic route
10:00-10:15 Jason Lin University of Texas at Dallas
Wrinkled Periodic Mesoporous Organosilica Nanoparticles for Hydrophobic Drug Delivery
10:15-10:30 Juan P. Vizuet University of Texas at Dallas
Metal-organic Frameworks in Polymeric Membranes for Gas Separations
Inorganic/Materials Chemistry 1A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 25
Neodymium based Complexes bearing Phosphate Ligands for Living
Ring Opening Polymerization of ε-Caprolactone and D, L-lactide
Yixin Ren, Stephanie T. P olderman, Trinh D. Vo, Michael C. Biewer and Mihaela C. Stefan*
Department of Chemistry and Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Polymer Chemistry
Neodymium-based complexes bearing phosphate ligands NdCl3·3L (L = triethyl phosphate (TEP) or
tris(2-ethylhexyl) phosphate (TEHP) were successfully synthesized. The ring opening polymerization
(ROP) of ε-caprolactone (ε-CL) and D, L-lactide (LA) initiated with these complexes in the presence
of a series of alcohols were performed yielding polymers with narrow polydispersity index (PDI =
1.22 to 1.47) and well-defined molecular weights. An important result from the kinetic studies
revealed that the sterically bulkier ligand TEHP as compare to TEP ligand scientifically increase the
rate for ROP of ε-CL. Di-block copolymers poly(ε-caprolactone)-block-poly(D, L-lactide) via sequential
monomers addition were successfully synthesized and demonstrated the livingness of the catalytic
system.
Inorganic/Materials Chemistry 1A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 26
Resolving Crystallographic Disorder in Intermetallics Adopting the
Yb3Rh4Sn13-Structure Type
Iain W. H. Oswald,1 Binod K. Rai,2 Emilia Morosan,2 Julia Y. Chan1*
1Department of Chemistry and Biochemistry, University of Texas at Dallas
2Department of Physics and Astronomy, Rice University
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Electrical and magnetic properties of solid-state materials are inherently tied to their structure and are
thus affected by defects or disorder. Presented herein is a crystallographic study on a series of
superconducting compounds, Ln3T4Ge13 (Ln = Y, Lu, Yb; T = Os, Ir, Co, Rh), adopting the Yb3Rh4Sn13-
structure type. This structure is modeled in the cubic space group Pm3̅n with lattice constant aprimitive ~
8.9 Å, consisting of corner sharing Ge icosahedra and transition metal trigonal prisms. Single crystal X-
ray diffraction experiments revealed anomalous elongated ellipsoids, indicating the presence of static
disorder. Additionally, weak, unindexed reflections were also observed in powder X-ray diffraction,
suggesting the structure has lower symmetry. A crystallographic model is proposed for the structure of
Ln3Ir4Ge13 (Ln = Lu, Yb) with tetragonal space group I41/amd, where atetragonal ~ 2aprimitive that accounts for
these distortions. Additionally, an empirical correlation between the semiconducting-like electrical
resistivity and atomic displacement parameters (ADPs) was found. These results suggest disorder,
quantified by ADPs, can be used as a new tool for predicting physical properties of a material.
Inorganic/Materials Chemistry 1A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 27
Asymmetric Catalysis by Chiral Metal Clusters
Darrell D. Mayberry, Michael G. Richmond*
Chemistry Department, University of North Texas,
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
The reactions of 1-(3-(diphenylphosphino)ethylthiol)-2- (diphenylphosphino)benzene (dppet) and 1-(3
(diphenylphosphino)ethoxy)-2-(diphenylphosphino)benzene (dppeo) with (μ-H)2Ru3(μ3-S)(CO)9 along with
their corresponding chiral cluster products were investigated for use in asymmetric catalysis. The chiral
cluster products from the aforementioned reactions produced (μ-H)2Ru3(μ3-S)(CO)6(μ3-dppet) (1), (μ-
H)2Ru3(μ3-S)(CO)7(μ-dppet) (2), (μ-H)2Ru3(μ3-S)(CO)7(μ- dppeo) (3). Clusters 1, 2, and 3 were
characterized by NMR spectroscopy; in addition, X-ray diffraction analysis of cluster 1 was performed.
VT-NM spectroscopy confirmed the carbonyl ligand fluxionality in 13C-enriched clusters 1, 2, and 3.
Thermolysis was used to establish the conversion of cluster 2 to cluster 1. A catalytic mechanism
involving clusters 1, 2, and 3 was investigated by DFT calculations.
Inorganic/Materials Chemistry 1A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 28
Hydrophobic Fluorinated Polymers for Corrosion Protection on
Aluminum Surface
Waleed Yaseen, Sreekar Marpu, Mohammad A. Omary*, Teresa Golden*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Hydrophobic and corrosion resistive coatings were successfully prepared by photopolymerization of
acrylate based fluorinated monomers. The coatings are directly cured on aluminum surface by simple
drop cast technique. Poly hexafluoroisopropyl methacrylate (PHFiPMA) and poly hexafluorobutyl
methacrylate (PHFBMA) were prepared by free radical photopolymerization method. Hexafluorobutyl
methacrylate (HFBMA) and hexafluoroisopropyl methacrylate (HFiPMA) were used as monomers,
hydroxycyclohexyl phenyl ketone (Irgacure 184) as a photoinitiator, and poly (ethylene glycol) diacrylate
as a cross-linker. These fluorinated polymers demonstrated highly corrosion protection characterized
by using Potentiodynamic polarization, open circuit potential (OCP), and electrochemical impedance
spectroscopy (EIS) techniques in 3.5% NaCl solution. Flourier transform infrared spectroscopy (FTIR)
and Scanning Electron Microscope (SEM) techniques were used to show the structure and the
morphology of the coatings surface. Dynamic contact angle test demonstrated the hydrophobicity of the
fluorinated polymers. Thermal stability for these polymers was measured by using thermogravimetric
analysis (TGA). The in-house photopolymerized fluorinated polymers exhibited strong chemical resistance
for strong acids and bases as well as resistance for wide range of solvents. Tape test method was used
as well to show the adhesion strength of these coatings on the aluminum surface. The in-house technique
for making these fluorinated corrosive coatings is highly economical compared to very expensive
commercial polymers of similar category.
Inorganic/Materials Chemistry 1A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 29
Synthesis and characterization of novel copper phenanthroline complexes: Tuning the structure and photophisics via alteration of the
synthetic route
Mikaela Wilk, Shaquisha Scott, Daniella Vargas, Rebecca Johnson, Youstina Fateem, Vladimir
Nesterov, Manal Rawashdeh-Omary*
Department of Chemistry and Biochemistry, Texas Woman’s University
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Copper is a low cost abundant metal that is currently being studied for potential application in many
fields including medicinal treatments, solar energy, and catalysis. The synthetic route plays an important
role in differentiating 4 new copper phenanthroline complexes. This presentation will give an overview
of the synthesis, crystal structures, and photophysical properties of these complexes. Infrared
spectroscopy, nuclear magnetic resonance spectroscopy, thermogravimetric analysis, X-ray
crystallography, and UV/Vis electronic absorption and luminescence spectral data will be presented for
the products of the different reactions attempted vs. the starting material.
Inorganic/Materials Chemistry 1A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 30
Wrinkled Periodic Mesoporous Organosilica Nanoparticles for Hydrophobic Drug Delivery
Jason Lin, Kenneth Balkus Jr.*
Department of Chemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
There is a growing interest of utilizing mesoporous silica in numerous applications. Mesoporous silica
has several significant properties included high surface area, high capacity, tunable functionality, and
modifiable morphology. These characteristics make mesoporous silica a promising drug delivery
material.
Our wrinkled periodic mesoporous silica is basically synthesized through hydrothermal reaction with
TEOS and benzylsilanes. Two surfactants are used as template, CTAB and CPB which cause a significate
difference of the morphology. The particles size is normally around 100 nm after 24hr synthesis no
matter which surfactant is used. Recently, we are focusing on synthesizing bi-phenyl silanes wrinkle silica
which provides fluorescence property and can be used for imaging.
Inorganic/Materials Chemistry 1A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 31
Metal-organic Frameworks in Polymeric Membranes for Gas Separations
Juan P. Vizuet, Kenneth J. Balkus*
Department of Chemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Metal-organic frameworks (MOFs) are porous, stable and highly ordered materials with high surface
areas. By carefully selecting the metal center and the organic linker used in the framework we can tailor
the specific properties of the MOF to match gas separation applications. The downside of these
materials is their high cost of production, processability and low mechanical stability when used as stand-
alone membranes.
Polymeric membranes have the advantages of low cost, processability and mechanical stability but they
have a tradeoff between gas permeability and selectivity. To overcome this tradeoff strategies like
polymer blending or addition of inorganic additives, such as MOFs, have been used. Furthermore, our
research has demonstrated that by using MOFs in a blend of non-compatible polymers, we can control
the internal morphology of the membrane.
My research focuses on the synthesis of novel Metal-organic Frameworks to use as additives in polymer
blend membranes. Selection of the appropriate synthetic conditions and the type of functional groups in
the organic linker are key to obtain suitable materials that can be used as additives. After the synthesis
of the MOFs, construction of membranes is the next step in my research.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 32
Section 2
Inorganic/Materials Chemistry 2A Sid W. Richardson Physical Sciences Building: Lecture Hall 3
Time Presenter Title
11:00 -11:15 Yakun Cao Southern Methodist University
Synthesis and Utilization of 1-Chloro-2-methyl-1,8-benziodazol-3(2H)-one in the Preparation of Hyperbranched Polymers
11:15-11:30 Lauren M. Harris University of North Texas
Monovalent coinage metal diphosphine-based complexes as potential led phosphors for display technologies
11:30-11:45 Samantha M. Brewer Texas Christian University
Catalytic and mechanistic investigation of three tetra-aza macrocyclic iron(III) complexes
11:45-12:00 Philip M. Palacios University of Texas-Arlington
The Kinetic and Spectroscopic Characterization of 2-aminoethanethiol dioxygenase
12:00-12:15 Wijayantha A. Perera University of Texas at Dallas
Hydrothermal Synthesis of TiO2 Nanotube (TNT)/ RuO2 Nanoribbon (NR)/ Graphene Oxide Composites with Enhanced Photocatalytic Activity
12:15-12:30 Erin N. Benton University of North Texas
Sensing Silver Ion Leakage from Silver Nanoparticles
Inorganic/Materials Chemistry 2A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 33
Synthesis and Utilization of 1-Chloro-2-methyl-1,8-benziodazol-3(2H)-one in the Preparation of Hyperbranched Polymers
Yakun Cao, Nicolay V. Tsarevsky*
Department of Chemistry and Center for Drug Discovery, Design, and Delivery at Dedman
College, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Polymer Chemistry
Hyperbranched polymers have received enormous amount of attention due to their unique properties
such as abundant functional groups, intramolecular cavities, low viscosity as well as their potential
applications in coatings, additives, drug and gene delivery. A new hypervalent iodine compound, 1-chloro-
2-hexyl-1,8-benziodazol-3(2H)-one (CHIO), was synthesized and utilized as both, an initiator and a transfer
agent, to prepare highly branched polymers with numerous alkyl chloride chain ends. CHIO can cleave
homolytically upon thermal conditions to produce chlorine radicals which can be utilized to polymerize
vinyl-monomers. Furthermore, in presence of propagating radicals, CHIO can act as transfer agent by
transferring the chlorine atom to the propagating chain. Thus, the facile synthesis of branched polymers
in high yields with significant delay in gelation was achieved. In addition, the effects on polymerization of
CHIO concentration, solvents and temperature were systematically investigated.
Inorganic/Materials Chemistry 2A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 34
Monovalent coinage metal diphosphine-based complexes as potential
LED phosphors for display technologies
Lauren M. Harris, Mukunda M. Ghimire, and Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
This work focuses on the design and syntheses of monovalent transition coinage metal-based functional
materials that exhibit potential to be used in energy applications, including energy saving, harvesting, and
storage. Finding efficient, low-cost phosphorescent materials based on these late transition metal
complexes has been a focal point of this study. Additionally, this work can possibly serve a number of
modern display technological applications, especially inorganic and organic light emitting diodes (LEDs
and OLEDs, respectively). Because of high spin−orbit coupling (SOC) induced by the coinage metal(I)
centers, and high radiative triplet decay rates if applied in OLEDs, these complexes can exploit both the
singlet and triplet excitons and, principally, can transfer them into light with 100% internal quantum yield.
The reaction of a monovalent coinage transition metal precursor with diphosphine ligands leads to the
corresponding coordination complexes in high yield. Synthetic details, single crystal X-ray solid-state
structures and other relevant characterization techniques such as NMR, FTIR, UV/Vis/NIR solution
absorption, solid-state diffuse reflectance, and solid-state photoluminescence spectroscopies will be
explored. These complexes exhibited blue, turquoise, and green photoluminescent emissions with high
quantum yields, which are desired properties to address the existing problems with respect to the blue-
light emission of LEDs and OLEDs.
Inorganic/Materials Chemistry 2A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 35
Catalytic and mechanistic investigation of three tetra-aza macrocyclic iron(III) complexes
Samantha M. Brewer, Kayla N. Green*
Department of Chemistry & Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Iron plays a pivotal role in metabolism and transport processes in nature but can also be used
to accomplish important chemical transformations on the bench top; recently, iron(II) salts have
been shown to catalyze direct Suzuki – Miyaura coupling of N-heterocyclic compounds and
arylboronic acid derivatives in the presence of oxygen. Presented herein are three tetra-aza
macrocyclic iron(III) complexes [L1Fe(III)(Cl)2]+ (L1Fe), [L2Fe(III)(Cl)2]+(L2Fe), and
[L3Fe(III)(Cl)2]+ (L3Fe) [L1 (Pyclen)=1,4,7,10-tetra-aza-2,6-pyridinophane; L2 =3,6,9,15-
tetraazabicyclo[9.3.1]penta-deca-1(15),11,13-trien-13-ol; L3 =3,6,9,15-tetra-
azabicyclo[9.3.1]penta-deca-1(15),11,13-trien-12-ol] that catalyze the coupling of pyrrole and
phenylboronic acid. Following the synthesis and reactivity studies, investigation into the oxidation
state of the iron center throughout the catalytic cycle was explored. The results of this work to
date will be presented and will facilitate the understanding of challenging chemical reactions
catalyzed using inexpensive earth abundant metals such as iron.
Inorganic/Materials Chemistry 2A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 36
The Kinetic and Spectroscopic Characterization of 2-aminoethanethiol dioxygenase
Philip M. Palacios, Brad S. Pierce*
Department of Chemistry, University of Texas-Arlington
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Non-heme enzymes have historically received strong interest in the field of bioinorganic chemistry due
to their widespread functionalities and structural diversity. 2-aminoenthanethiol dioxygenase (ADO) is a
non-heme, mononuclear iron enzyme that catalyzes the O2-depedent oxidation of cysteamine (CA) to
produce hypotaurine (HTau). Coincidentally, very little information is available in the literature regarding
the mechanism and characteristics of this enzyme. In this work, we present steady-state kinetics of ADO
with two different thiol substrates, cysteine (Cys) and cysteamine (CA) as a means to determine the
kinetics of the enzyme with its native substrate. Taken together with EPR spectroscopy, we present a
model for cysteamine oxidation.
Inorganic/Materials Chemistry 2A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 37
Hydrothermal Synthesis of TiO2 Nanotube (TNT)/ RuO2 Nanoribbon
(NR)/ Graphene Oxide Composites with Enhanced Photocatalytic
Activity
Wijayantha A. Perera, Yuzhi Gao, Yves Chabal, Kenneth J.Balkus Jr*
Department of Chemistry and Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Titanium dioxide is the most studied and widely used photocatalyst. In the presence of Uv light, it
generates electrons and holes that can act as a powerful oxidizing and reducing species. But 99% of
the generated electrons and holes recombine before they react with the pollutants. This will limit its
photocatalytic performance. Therefore, the goal is to minimize the electron-hole recombination. A new
method have been introduced to separate generated electrons and holes by using graphene oxide/
ruthenium oxide nanoribbons/ titanium dioxide nanotube composite. Different amounts of ruthenium
oxide nanoribbons and titanium dioxide nanotubes were grown on reduced graphene oxide and evaluated
its photocatalytic efficiency using malachite green oxalate dye. The composite with highest loading
showed excellent photocatalytic performance.
Inorganic/Materials Chemistry 2A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 38
Sensing Silver Ion Leakage from Silver Nanoparticles
Erin N. Benton, Sreekar Marpu, Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Silver nanoparticles have many applications including drug delivery, antimicrobial behavior (numerous
products of which are available in the market), and biological imaging. There have been numerous
studies/debates on the toxicity of silver nanoparticles versus silver ions and it is believed by some that
the toxicity may be due to the decay of the nanoparticles into silver ions. A gold(I) complex has been
developed that has the ability to differentiate between silver ions and silver nanoparticles in aqueous
solution. It was shown that silver nanoparticles leak silver ions over time and the sensor developed can
sense that release. The lower detection limit of this sensor was found to be 13.5ppb and the upper
detection limit was found to be 26.3ppm, which is competitive with other silver sensors found in the
literature.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 39
Section 2
Inorganic/Materials Chemistry 3A Sid W. Richardson Physical Sciences Building: Lecture Hall 3
Time Presenter Title
01:30 -01:45 Brooke M. Otten University of North Texas
To Be or Not To Be: d10-d10 Bonding in Heterometallic Complexes
01:45-02:00 Avichal Vaish Southern Methodist University
Preparation of Self-healing & Dynamic Gels and Their Conversion to Non-Dynamic Gels using Hypervalent Iodine Compound
02:00-02:15 Seyed Majid Farvid University of North Texas
Improving the performance of prototypical bi-layer devices by a novel double-doping method
02:15-02:30 Katherine A. Benavides University of Texas at Dallas
Property-Driven Synthesis: The Relationship Between Structure and Properties of Ln2Fe4-xCoxSb5 (Ln = La – Pr; x < 1.5)
02:30-02:45 Do Nguyen University of Texas at Dallas
Improved Hydrogen Separation Performance of Mixed-Matrix Membranes based on Blend of Immiscible Polymers
Inorganic/Materials Chemistry 3A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 40
To Be or Not To Be: d10-d10 Bonding in Heterometallic Complexes
Brooke M. Otten, Mohammad M. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Heterometallic and homometallic complexes of the form [MM`PCPx] (where M= Ni, Pd and Pt;
PCP=PH2CH2PH2 and x=2 or 3) have been modeled using density functional theory to determine if these
complexes display metal-metal bonding. While the homometallic complexes show conventional bond
orders of zero, the heterometallic complexes show bond orders that are not equal to zero. For all
complexes, the optimized geometries were examined to find metal-metal distances and Dunham analysis
was performed on the potential well to find the metal-metal vibrational frequencies. Orbitals were also
analyzed to determine the bond orders. In homometallic complexes, it was found that the mixing of nd-
nd orbitals give rise to 5 bonding orbitals and 5 antibonding orbitals while the heterometallic complexes
exhibit occupied non-bonding orbitals. The occupancy of the non-bonding orbitals leads to complexes with
shorter metal-metal distances and higher dissociation energies. However, the complexes with 3 bridging
ligands have shorter metal-metal distances which give stretching frequencies that are close to their 2
bridging ligand counterparts.
Inorganic/Materials Chemistry 3A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 41
Preparation of Self-healing & Dynamic Gels and Their Conversion to Non-Dynamic Gels using Hypervalent Iodine Compound
Avichal Vaish, Nicolay V. Tsarevsky*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Polymer Chemistry
In modern organic chemistry, hypervalent iodine(III) compounds are frequently used as oxidizing agents
but application of λ3-iodanes in polymer and material chemistry is still underexplored. In this work, we
report on the preparation of dynamic and self-healing materials by employing ligand exchange reactions
involving hypervalent iodine(III) compounds of the type ArIL2 (Ar = Aryl, L = ligand, e.g., carboxylate or
(pseudo)halide). These compounds can undergo ligand exchange reactions in presence of nucleophiles
(Nu-) to form ArINu2. Diacetoxyiodo benzene (DAIB) was successfully employed as a crosslinker to
prepare dynamic and self-healing gels derived from carboxylate-containing polymers. Furthermore,
advantage was taken of the ability of DAIB to generate radicals upon UV light irradiation in order to
convert the dynamic crosslinked structures to permanent (set) networks.
Inorganic/Materials Chemistry 3A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 42
Improving the performance of prototypical bi-layer devices by a novel
double-doping method
Seyed Majid Farvid, Dieaa Alhmoud, Musafa Kharma, Kurt Bodenstedt, Abdel Monem
Rawashdeh, and Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
We have discovered that standard NPB/Alq3 bi-layer organic light-emitting diodes (OLEDs) – the
prototypical devices that revolutionized OLEDs since the 1980s – can undergo a significant
improvement in performance upon slight alteration of the device structure. The novel approach entails
adding two doped layers sandwiched between the neat hole-transporting layer (NPB) and the electron-
transporting/light-emitting layer (Alq3). We have used two figures of merit to evaluate these devices, the
current at 10 V (I10) and turn-on voltage defined as the voltage to produce a significant current of 0.1
mA (V0.1) just beyond the baseline so that a good signal-to-noise ratio is ascertained. Device data surmise
that the double-doped devices exhibit 57% higher luminance current and 34% lower turn-on voltage
versus the neat undoped standard devices. There are three possible reasons behind this significant
finding:
a) The interface is smoothed between the two neat (undoped) layers of pure NPB and pure Alq3.
b) The carrier injection barrier is reduced in the double-doped device.
c) Broadening of the light-emitting interface or recombination zone.
As a consequence of the phenomena above, electrons and holes will have better abilities to surpass the
neat layers in the double-doped devices, offering broader light-emitting recombination zone versus
undoped bilayer devices.
Inorganic/Materials Chemistry 3A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 43
Property-Driven Synthesis: The Relationship Between Structure and Properties of Ln2Fe4-xCoxSb5 (Ln = La – Pr; x < 1.5
Katherine A. Benavides, Joseph V. Burnett, Sheng Li, Bing Lv, Julia Y. Chan*
Department of Chemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Single crystals of Ln2Fe4-xCoxSb5 (Ln = La – Pr; x < 1.5) were grown by the flux growth technique. The
structure is comprised of Ln-capped square nets of antimony and a triangular network of transition
metals. The electrical resistivities as a function of temperature are highly dependent on Co
concentration. In this presentation, the synthesis and structure of Ln2Fe4- xCoxSb5 will be compared
to other ternary antimonides and the electrical properties of Ln2Fe4-xCoxSb5 will be discussed.
Inorganic/Materials Chemistry 3A Sid. Richardson Lecture Hall 3
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 44
Improved Hydrogen Separation Performance of Mixed-Matrix Membranes based on Blend of Immiscible Polymers
Do Nguyen, Nimanka Panapitiya, Inga H.Musselman, Kenneth J. Balkus, John P. Ferraris*
Department of Chemistry and Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Polymer Chemistry
Mixed-matrix membranes (MMMs) has showed to be one of the best strategies to improve gas
separation properties of polymeric membranes. In this work, we proposed the use of immiscible blends
of high performance polymers to serve as the matrices for MMMs. Inherent macroscopic phase-
separation of immiscible polymer blends was strategically controlled with the incorporation of
nanoparticles ZIFs, a subclass of metal-organic frameworks (MOFs). Thorough characterization of the
MMMs was carried out to ratify the proposed proposition. In term of morphology control, the domain
sizes of the dispersed phases significantly decreased and became more uniform upon increase addition
of nanoparticles ZIFs from 0% to 20%. Promising gas separation properties were achieved with the
MMM composed of 20% nanoparticles ZIFs for H2/CO2, H2/N2, and CO2/CH4 gas pairs. Binary gas-
mixture separation performance will also be discussed.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 45
Section 3
Inorganic/Materials Chemistry 1B Sid W. Richardson Physical Sciences Building: Lecture Hall 2
Time Presenter Title
08:45-09:00 Alexander T. Brown University of Texas at Dallas
Synthesis and Stabilization of new intermetallic compounds Ln52Fe2Sn49 (Ln = Y, Gd, Tb, Dy)
09:00-09:15 Kortney M. Melancon University of North Texas
New Bond on the Rise: Ligand-Unassisted d10-d10 Bonding in Heterometallic Complexes
09:15-09:30 Tharun T. Ponduru University of Texas at Arlington
Selective catalytic functionalization of aromatic C(sp2)-H bonds
09:30-09:45 Brian L Kamras University of North Texas
Lecithin Liposome-Stabilized Gold Nanorods – A Multifunctional Platform for Targeted Treatment of Diseases
09:45-10:00 P. Sotelo University of Texas at Arlington
Exploratory Synthesis of Rare Earth Sulfides as Pigments
10:00-10:15 Joshua F. Ivy University of North Texas
Metal-Inorganic Frameworks (MIFs) from Phosphorescent Platinum Building Blocks
10:15-10:30 P.B Jayathilaka University of Texas at Dallas
Synthesis of smaller mesoporous silica nanoparticles to facilitate lymph node targeted drug delivery
Inorganic/Materials Chemistry 1B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 46
Synthesis and Stabilization of new intermetallic compounds Ln52Fe2Sn49
(Ln = Y, Gd, Tb, Dy)
Alexander T. Brown, Keaton G. Barron, Randall P. Kirby, Julia Y Chan*
Department of Chemistry and Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Single crystals of the new structure type Ln52Fe2Sn49 (Ln = Gd, Tb, Dy) are grown from a self-flux method
using the Ln-Fe binary eutectic point. The compounds are grown using a reaction ratio of 12 Ln : 3 Fe :
11 Sn and annealed at 1260 °C. In ambient conditions, the surface is silver with a metallic luster for the
first 12 h., then a passivation layer forms on the crystal surface. The crystal structures as determined
at 100 K were solved by the intrinsic phasing method. The Dy51.7Fe2Sn48.6 crystal structure is modeled in
space group Fmmm with lattice parameters a = 16.2992(6) Å, b = 16.9088(6) Å, c = 39.0656(14) Å,
V = 10766.5(7) Å3 with Z = 4. Ln52Fe2Sn49 has a large cell volume, structural complexity, and consists
of ten Ln, two Fe, and fourteen Sn unique crystallographic sites.
Inorganic/Materials Chemistry 1B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 47
New Bond on the Rise: Ligand-Unassisted d10-d10 Bonding in
Heterometallic Complexes
Kortney M. Melancon, Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Where intramolecular d10-d10 interactions in hetero- and homometallic structures have been extensively
studied, our work is focused on efforts to revisit and expand on metal-metal bonding in complexes of the
form MM’(MTP)2 and MM’(dppm)n (where M/M’=Cu/Au or Ag/Au and MTP=
diphenylmethylenethiophosphinate) and MM’(dppm)n (where M/M’=Ni/Pd, Pt/Pd, or Pd/Ni and n= 2
or 3 and dppm= bis(diphenylphosphinomethane). All complexes were modeled using density functional
theory to determine if heterobimetallic d10-d10 interactions are involved. Optimized geometric structures
were examined to determine metal-metal distances. Dunham analysis was performed on the potential
well to determine metal-metal vibrational frequencies in addition to molecular orbital modeling to
determine bond order. It was found that PtNi(dppm)2 and PdNi(dppm)2 give theoretical bond orders of
zero, whereas PtPd(dppm)n, PtNi(dppm)3, PdNi(dppm)3, AuAg(MTP)2, and AuCu(MTP)2 give non-zero bond
orders. This investigation serves as a comprehensive study of new metal-metal bonds discovered in the
complexes discussed above and our efforts to develop new synthetic routes to achieve these [MM’(μ-
L)n]m d10 structures.
Inorganic/Materials Chemistry 1B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 48
Selective catalytic functionalization of aromatic C(sp2)-H bonds
Tharun T. Ponduru, H.V. Rasika Dias*
Department of Chemistry and Biochemistry, University of Texas at Arlington,
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
The selective activation of unactivated aryl C(sp2)-H bonds is one of the most important challenging
processes in both academia and industry. There are several methods for this C-H bond activation,
among these selective and catalytic oxidation routes are particularly sought after because they
provide the simplest way to produce many industrially valuable chemicals from readily available
constituents of petroleum feedstocks. Indeed, a number of very important industrial processes are
currently in operation for this purpose. However, these processes often require harsh conditions,
strong acids and suffer from low selectivity usually due to over-oxidation. Thus, there is clearly a need
for a more efficient, milder, and environmentally friendly methodology. In our research, we would like
to investigate these processes using Copper adducts of fluorinated triazapentadiene ligands
[TAPxCu(NCMe)] as catalysts because they can last longer and tolerate highly oxidizing conditions.
We have found that these complexes catalyze the oxidation of benzene into phenol selectively using
0.5% catalyst loadings and for the conversion of anthracene into anthraquinone (87% isolated yield)
using 4% catalyst loadings. Particularly, our system does not require any acidic medium and
operates under mild conditions. Studies to ascertain the mechanism that governs these
transformations is currently underway in our laboratory.
Inorganic/Materials Chemistry 1B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 49
Lecithin Liposome-Stabilized Gold Nanorods – A Multifunctional
Platform for Targeted Treatment of Diseases
Brian L Kamras, Sreekar Marpu, Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Gold Nanorods are intensely studied for their numerous diagnostic, imaging and therapeutic
applications. However, a critical failing of commercially produced gold nanorods is their universal
cytotoxicity due to the use of the stabilizer cetyltrimethylammonium bromide (CTAB). High quality gold
nanoparticles (dia. ~9 nm, D = 0.343, A = 517 nm) have been formed by controlled decomposition of a
Au(I) complex in the presence of crude soy lecithin, which were added to a growth solution of the very
same Au(I) complex in addition to potassium bromide and a reducer. This resulted in the formation of
lecithin-stabilized gold nanorods with longitudinal surface plasmon resonances finely tunable from 690
nm to 860 nm. Additionally, the liposomal lumen can be actively loaded with a range of materials (small
molecules, proteins, DNA, etc.) The particles were stable for approximately three weeks at room
temperature. Currently, the cytotoxicity and photothermal activity of these nanoparticles towards model
human cell lines are being investigated.
Inorganic/Materials Chemistry 1B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 50
Exploratory Synthesis of Rare Earth Sulfides as Pigments
P. Sotelo, M. Orr, R. T. Macaluso*
Department of Chemistry and Biochemistry, University of Texas at Arlington,
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Cadmium sulfoselenide and compounds such as lead molybdate are currently among the most widely
used pigments of this kind.1 These compounds have excellent performance characteristics, but their
toxicity is environmentally undesirable. Rare-earth sulfides and related compounds have been proposed
as promising candidates2-4, however, their syntheses involve the flow of toxic and corrosive gases and
long, complicated heating procedures5. Here, we explore the synthesis, structure and optical properties
of ALn2S4 (A = Ca, Sr, Ba; Ln = La, Ce, Pr) as alternative inorganic pigments. Our synthesis strategies
are simpler and eliminate the flow of any gases. In addition, we have optimized our synthetic strategies
based on polymorph of the starting materials. Laboratory and synchrotron X-ray diffraction, along with
scanning electron microscopy, have been used to correctly identify the phases and crystal structures of
these materials. Diffuse reflectance spectroscopy experiments have been performed to characterize
optical properties. Differential scanning calorimetry shows that ALn2S4 (A = Ca, Sr, Ba; Ln = La, Ce, Pr)
are stable up to ~5oo°C, which means that these materials may be potentially useful in widespread
plastic and paint applications.
This work has been supported by the American Chemical Society Petroleum Research Fund
Grant #52309-ND10 and the National Science Foundation CAREER Award #1541230.
References:
1. Maestro, P.; Huguenin, D., Industrial applications of rare-earths - which way for the end of the century. Journal of Alloys and Compounds 1995, 225 (1-2), 520-528. 2. Urones-Garrote, E.; Martinez, F. F.; Landa-Canovas, A. R.; Otero-Diaz, L. C., New inorganic pigments in the Ca-Nd-S system: Stabilization of gamma phase. Journal of Alloys and Compounds 2006, 418 (1-2), 86-89. 3. Perrin, M. A.; Wimmer, E., Color of pure and alkali-doped cerium sulfide: A local-density-functional study. Physical Review B 1996, 54 (4), 2428-2435. 4. Hernandez-Alonso, M. D.; Gomez-Herrero, A.; Landa-Canovas, A.; Duran, A.; Fernandez-Martinez, F.; Otero-Diaz, L. C., New ecological pigments in the Ca-Yb-S system. Journal of Alloys and Compounds 2001, 323, 297-302. 5. Flahaut, J.; Guittard, M.; Patrie, M.; Pardo, M. P.; Golabi, S. M.; Domange, L., phases cubiques type Th3P4 dans les sulfures les seleniures et les tellurures L2X3 et L3X4 des terres rares et dans leurs combinaisons ML2X4 avec les sulfures et seleniures mx de calcium strontium et baryum . Formation et proprietes cristallines. Acta Crystallographica 1965, 19, 14-&.
Inorganic/Materials Chemistry 1B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 51
Metal-Inorganic Frameworks (MIFs) from Phosphorescent Platinum
Building Blocks
Joshua F. Ivy, Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Pt-based Inorganic building blocks were used to generate a new series of extended solids. Two series of
complexes, one based on previously-studied Pt-POP ([Pt2(P2O5)4]-4) and the other based on new metal-
carboxylate ligands have been synthesized. These materials belong to a new class of metal-inorganic
frameworks (MIFsTM) that have been designed for the purposes of functional applications such as gas
adsorption and storage, catalysis, and optoelectronics (U.S. Provisional Patent Application
62/332,292). Materials were analyzed by X-ray diffraction, low-pressure nitrogen adsorption
isotherms, UV-Vis diffuse reflectance, and photoluminescence spectroscopy. Each MIF was contrasted
with its precursor complex to determine changes in photoluminescence properties upon complexation
with additional metals. Zr(IV) and Zn(II)-based MIFs of Pt-POP showed enhanced luminescence properties
and drastically enhanced environmental stability compared to the solid starting material with non-
coordinating counterions. The zirconium-Pt-POP complex showed moderate porosity.
Inorganic/Materials Chemistry 1B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 52
Synthesis of smaller mesoporous silica nanoparticles to facilitate
lymph node targeted drug delivery
P.B Jayathilaka, Kenneth J. Balkus Jr.*
Department of Chemistry, The University of Texas at Dallas,
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Lymph nodes are one of the main targets of many cancer vaccines as antigens are captured by dendritic
cells in lymph nodes and initiate cellular immune responses. Various studies have been carried out to
develop nanoparticles to encapsulate antigens to protect them from the degradation and extend contact
time with the immune system. It also helps to improve their delivery to dendritic cells and lymph nodes.
However, the uptake of nanoparticles into lymph nodes depends on their particle size. Smaller
nanoparticles (size 10 and 100 nm) are more preferred and efficient than large size nanoparticles for
targeting lymphatic nodes. Therefore, this study was focus to develop smaller mesoporous silica
nanoparticles (MSp) to facilitate lymph node targeted drug delivery. MSp were synthesized by using soft
template method and the resulted particles were within the size ranging from 35 nm to 50 nm. They
were characterized with transmission electron microscope (TEM), scanning electron microscope (SEM)
and the N2 sorption isotherm and Barrett-Joyner-Halenda (BJH) pore size distribution measurements.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 53
Section 3
Inorganic/Materials Chemistry 2B Sid W. Richardson Physical Sciences Building: Lecture Hall 2
Time Presenter Title
11:00 -11:15 Daniel Korir University of North Texas
Facile Photochemical Synthesis and Properties of conjoined gold-silver Nanoparticles with tunable Plasmonic absorption
11:15-11:30 Hannah Johnston Texas Christian University
Synthesis and characterization of novel manganese monomers and dimers with tetraazamacrocyclic ligands
11:30-11:45 Ruaa Almotawa University of North Texas
Synthesis and Characterization of Cu(I) and Ag(I) Complexes with Mixed Diphosphine and Diimine Ligands
11:45-12:00 Jonathan Buford University of Texas at Dallas
TiO2 Nanotubes Decorated with Ruthenium-based Nanoparticles
12:00-12:15 Christopher Williams University of North Texas
Novel Ambipolar Organic Fluorophores: A Computational/Experimental Investigation of Photophysical, Redox, and Conductive Properties
12:15-12:30 Kenneth J. MacKenzie Texas A&M University – Commerce
Investigation of Palladium Catalysts, for a Green Chemistry Approach to the Selective Hydrogenation of Diphenylacetylene
Inorganic/Materials Chemistry 2B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 54
Facile Photochemical Synthesis and Properties of conjoined gold-silver
Nanoparticles with tunable Plasmonic absorption
Daniel Korir, Sreekar Marpu, Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Plasmonic metal nanoparticles have been extensively studied for their unique optical properties arising
due to Localized Surface Plasmon resonance (LSPR). Especially, gold and silver nanoparticles with
tunable Surface Plasmon Resonances (SPR) have been studied for applications including Photo Thermal
Therapy (PTT), drug delivery, antimicrobial/ antipathogenic and sensor applications. This study overviews
the synthesis and surface enhanced Raman spectroscopy (SERS) of bifunctional conjoined gold- silver
nanoparticles (Ag-Au) different from well-established alloyed or core shell structures reported in the
literature. In this effort, we synthesized bimetallic nanomaterials within biocompatible
stabilizers/matrices following facile photochemical technique. Conjoined Ag-Au NPs retaining plasmonic
absorption of both metals are achieved using varied aspect ratios of gold seeds followed by careful
growth of silver as Nano-twin feed under similar photochemical conditions. The bimetallic nanoparticles
with tunable SPR are expected to exhibit synergetic properties of gold and silver beneficial for both
materials and biomedical applications.
Inorganic/Materials Chemistry 2B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 55
Synthesis and characterization of novel manganese monomers and
dimers with tetraazamacrocyclic ligands
Hannah Johnston, Kayla N. Green*
Department of Chemistry and Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Manganese containing enzymes are prevalent in nature; one specific example is the oxygen
evolving complex (OEC) located in photosystem II (PSII) of green plants. Due to the biological
relevance of manganese, model complexes with this transition metal are ubiquitous in the
chemical literature, particularly those modeling the OEC in PSII. Historically, OEC models
incorporate two multidentate nitrogen contain ligands coordinated to Mn(III) and Mn(IV)
connected by two bridging oxygens. Although rudimentary models, these bimetallic complexes
have shown the ability to perform several catalytic reactions. Recently, we have metalated
pyridine- and pyridol- containing macrocycles with manganese to form both the historically
significant Mn(III,IV) dimer complex as well as a Mn(III) monomer. A Mn(III,IV) dimer with a pyridol-
containing macrocyclic is the first of its kind synthesized to date. Characterization of both the
monomeric and dimeric manganese complexes, as it relates to the OEC includes: UV-Visible
spectroscopy, X-ray diffraction (XRD), cyclic voltammetry (CV), and electron paramagnetic
resonance (EPR). In the future, the catalytic activity of these complexes will be investigated.
Inorganic/Materials Chemistry 2B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 56
Synthesis and Characterization of Cu(I) and Ag(I) Complexes with
Mixed Diphosphine and Diimine Ligands
Ruaa Almotawa,a,b Kimberly Savage,a Fatemah Behnia,a Manal A. Rawashdeh-Omary,b,* Mohammad A.
Omary a ,*
a Department of Chemistry, University of North Texas
b Department of Chemistry and Biochemistry, Texas Woman’s University
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
A series of copper(I)/silver(I) ionic complexes containing bis[2-diphenylphosphino)phenyl]ether and
diimine ligands, including (pyrazine, 4’4-dipyridyl (bpy), 1,2-bis(4-pyridyl) ethylene (bpe), 4,4′-
trimethylenedipyridine (bpp), 1,2-bis(4-pyridyl)ethane (bpa), and 4’4-azopyridine (azopy)), and BF4 as an
anion has been synthesized. The complexes were characterized by X-ray diffraction, IR, luminescence,
NMR spectroscopy and thermal gravimetric analysis (TGA). The goal of this project is to provide novel
compounds that can be utilized in electronic and photonic materials. The chemistry of silver (I) and
copper (I) ions with N^N as a diimine ligand and P^P as a diphosphine ligand exhibits promising emissive
species. They are emerging as promising candidates for highly efficient emitters in organic light emitting
diodes (OLEDs).
Inorganic/Materials Chemistry 2B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 57
TiO2 Nanotubes Decorated with Ruthenium-based Nanoparticles
Jonathan Buford, Kenneth J. Balkus*
Department of Chemistry and Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
This research focuses on depositing ruthenium-based nanoparticles on the surface of TiO2 nanotubes,
with the intention of using these synthesized materials for photocatalysis. The inspiration for this project
stemmed from an interest in predicting the band gap of the TiO2 nanotubes (3.0eV-3.2eV) after the band
was bent by the ruthenium material.
These TiO2 nanotubes are formed via a hydrothermal synthesis, while the ruthenium is introduced in the
form of the salt RuCl3∙nH2O. The Ruthenium ions are bound to the nanotubes using thiolactic acid (TLA)
as a linker. The concentration of linker in solution also helps to regulate the sizes of the ruthenium-based
nanoparticles that are bound to the surface. Ruthenium nanoparticle attachment is accomplished with
use NaOH or Na2S to yield RuO2 or RuS2 nanoparticles respectively.
The synthesized TiO2 nanotubes with ruthenium-based nanoparticles are imaged with transmission
electron microscopy and the crystalline structure is displayed via X-ray diffraction. In conclusion the TiO2
nanotubes decorated with ruthenium-based nanoparticles were formed and the research in the future
will consist of changing the TLA concentration to adjust size and eventually use the for photocatalytic
purposes.
Inorganic/Materials Chemistry 2B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 58
Novel Ambipolar Organic Fluorophores: A
Computational/Experimental Investigation of Photophysical, Redox,
and Conductive Properties
Christopher Williams, Gustavo Salazar, Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
The photophysical properties of metal complexes with heterocyclic aromatic ligands have sparked great
interests in applications that range from solar energy conversion to LED phosphors. However, typical
heterocyclic aromatic ligands (e.g., bipyridine/phenanthroline/terpyridine) exhibit low extinction
coefficients, too-high absorption energies (mid-UV), and unipolar (n-type) charge transport
characteristics, all of which negatively impact their/their derivative’s use in optoelectronic devices.
Herein, UV-vis and photoluminescence properties are investigated for novel ambipolar organic
molecules/ligands containing an electron-rich N,N-diethylphenylamine group and an electron-poor
triazine core that bears two other N-donor azole (Az) substituents. This molecular design allows fine-
tuning the HOMO-LUMO energy through modifying the steric and/or electronic factors upon Az group
variation. TD-DFT calculations with M06 and B3LYP functionals were performed and attained excellent
qualitative agreement with experimental results. Analysis of frontier molecular orbitals and electron-
density distribution vs Az substituents was also implemented. Solvent effects on the photophysical
properties of these compounds will be presented for both the fluorophores per se and their adducts
with Re(I), taken as the first case study for metal complexes. Both computations and experiments
underscored the superiority of the novel molecules in terms of overcoming ALL aforementioned
limitations of conventional polyimine counterparts.
Inorganic/Materials Chemistry 2B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 59
Investigation of Palladium Catalysts, for a Green Chemistry Approach
to the Selective Hydrogenation of Diphenylacetylene
Kenneth J. MacKenzie, Jessica Velazquez, Syed S. A. Hussaini, Dr. Bukuo Ni, Dr. Ben Jang*
Department of Chemistry, Texas A&M University – Commerce
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
There has been a growing interest in catalyzed hydrogenation, as a means of chemical synthesis in the
pharmaceutical, petrochemical, and food industries. These industries use metal based catalysts as a
means of mass producing common chemical products (such as fats and oils, vitamin A, and polymeric
monomers). Using heterogeneous catalysts, alkynes can be selectively reduced to alkenes and not to
alkanes. With this research, we hope to analyze the conversion, and selectivity potentials of an array of
palladium catalysts in the hydrogenation of diphenylacetylene. We hypothesize that these catalysts can
be used to hydrogenate close to 100% of the substrate, to the cis- and trans- stilbene, without producing
significant amount of bibenzyl. The results show that high conversion and relatively low selectivity or high
selectivity and relatively low conversion can be obtained with the catalyst of 0.05%Pd supported on
alumina. This area of chemical synthesis, would allow industry to further employ the values of green
chemistry, by using recoverable catalysts, with close to 100% conversion and selectivity towards the
production of the desired product. This method of synthesis would lessen the production of wasteful
byproducts, minimize solvent use, and reduce reaction times.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 60
Section 3
Inorganic/Materials Chemistry 3B Sid W. Richardson Physical Sciences Building: Lecture Hall 2
Time Presenter Title
01:30 -01:45 Khaled Shennara University of North Texas
PPTT: Treating Cancer Cells
01:45-02:00 Mohammed Irfan Zakir Omer Texas A&M University Commerce
Mesoporous Catalysts for the Synthesis of Biodiesel
02:00-02:15 Anne D’Achille Texas Christian University
Suppression of Melanin Synthesis by Europium Doped Cerium Oxide Nanomaterials
02:15-02:30 Sinjinee Sardar University of Texas at Arlington
Kinetic and spectroscopic investigation of the catalytic triad of the non-heme mononuclear iron enzyme 3-mercaptopropionate dioxygenase from Azotobacter vinelandii (Av MDO)
02:30-02:45 Rajesh Kumar Southern Methodist University
Synthesis of Linear and Branched Polymers Utilizing Hypervalent iodine Compound
Inorganic/Materials Chemistry 3B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 61
PPTT: Treating Cancer Cells
Khaled Shennara, Mohammad A. Omary*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Photothermal therapy is a rising promise for treating different cancer cells. However, there are side
effects from this therapy, and thus our team is interested in technique development of PPTT using
metallic nanoparticles. The PPTT protocol will be developed upon a modification of the irradiation therapy
using two major changes. The first is using a less harmful visible light or a harmless near infrared light,
and the second is using gold-loaded biocompatible nanoparticles. Acrylate nanoparticles will be loaded
with desired types of gold nanoparticles at different sizes. The gold-loaded gold nanoparticles will be
conjugated to cancer cells. By selectively delivering the gold nanoparticles into cancer cells, irradiating a
harmless near infrared light will achieve a thermal ablation of the cancer cells. Based on imaging
spectroscopy and flow cytometry, results showed reduction of gold loaded-normal cancer cells upon
irradiating with a near infrared light, and no change in the number of cancer cells with irradiating with
light only.
Inorganic/Materials Chemistry 3B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 62
Mesoporous Catalysts for the Synthesis of Biodiesel
Mohammed Irfan Zakir Omer , Syed Shah Abdullah Hussaini and Syed Zia, Dr. Ben Jang*
Department of Chemistry, Texas A&M University – Commerce
E-mail: [email protected]
Category: Graduate
Division: General Chemistry
Depletion of fossil fuel has been a big threat to humans along with environmental pollution, the interest
to create and use plant oils and animal fats as biodiesel has been constrained up to these years and
now has been put into use. In this paper starch is investigated as the precursor to synthesize various
mesoporous catalysts with pore size 2 – 50 nm, for the esterification of oleic acid with methanol as the
probe reaction for the production of biodiesel. The results show that the activity of mesoporous catalysts
is a function of surface properties such as surface areas, porosity, acid density, etc. and the functional
groups attached to the structure can be depicted by Fourier Transform Infrared Spectroscopy, acid-
base titration and Nuclear Magnetic Resonance Spectroscopy It is concluded that careful attention is
needed during each stage of catalyst preparation, such as gelatinization, retrogradation, exchange,
drying, and sulphonation, to result in catalysts with high acid density values for the production of biodiesel.
Inorganic/Materials Chemistry 3B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 63
Suppression of Melanin Synthesis by Europium Doped Cerium Oxide
Nanomaterials
Anne D’Achille, Jeffery Coffer*
Department of Chemistry and Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
Nanomaterials based on cerium (IV) oxide, CeO2, have been investigated due to interesting chemistry
from a readily available transition between Ce3+ and Ce4+. This transition, along with oxygen vacancies
present in the oxide lattice, give CeO2 materials antioxidant and enzyme mimetic behavior.i Doping with
trivalent, fluorescent ions such as Eu3+ further increases the oxygen vacancy concentration, controls the
Ce3+/Ce4+ ratio, and may add fluorescence to the doped material.ii
Eumelanin is a complex dark brown pigment originating from the oxidation and oligimerization of tyrosine
or through the auto-oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA). The pigment’s antioxidant
activity, strong UV-VIS absorption, and conductive properties give it potential applications in radiation
damage protection, and treatment of Parkinson’s and Alzheimer’s disease.iii
Our research thus far has focused on the controlled synthesis of various EuCeO2 materials, and their
interaction with the auto-oxidation of L-DOPA to eumelanin. EuCeO2 nanorods and nanocubes were
synthesized through a hydrothermal reaction of precipitated EuCe(OH)3. Nanowires were synthesized
using electrospinning and annealing techniques.
The presence of CeO2 or EuCeO2 materials consistently suppressed the eumelanin-associated
fluorescence intensity. Temperature, pH, nanomaterial concentration/morphology, and europium
dopant concentration were all evaluated for potential impact on the evolution of eumelanin from L-DOPA
in the presence of EuCeO2 nanomaterials.
References
i Xu, C.; Qu, X. NPG Asia Materials, 2014, 6, 1-16 ii Kumar, A.; Babu, S.; Karakoti, A.S.; Schulte, A.; Seal, S. Langmui,r 2009, 25(18), 10998–11007 iii Sutter, J. ; Birch, D. Methods Appl. Fluoresc. 2014, 2, 024005
Inorganic/Materials Chemistry 3B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 64
Kinetic and spectroscopic investigation of the catalytic triad of the non-
heme mononuclear iron enzyme 3-mercaptopropionate dioxygenase
from Azotobacter vinelandii (Av MDO)
Sinjinee Sardar, Andrew Weitz, Michael Hendrich and Brad S. Pierce
Department of Chemistry and Biochemistry, University of Texas at Arlington
Department of Chemistry, Carnegie Mellon University Pittsburg
E-mail: [email protected]
Category: Graduate
Division: Inorganic Chemistry
3-mercaptopropionate dioxygenase from Azotobacter vinelandii (Av MDO) is a non-heme mononuclear
iron enzyme that catalyzes the O2-dependent oxidation of 3-mercaptopropionate (3mpa) to form 3-
sulfinopropionic acid (3spa). Within the MDO active site three outer sphere Fe-coordination residues
S155, H157 and Y159 is observed. This “catalytic triad” is universally conserved among all known thiol
dioxygenase enzymes across the phylogenic domain but their role in catalysis is yet to be understood. In
this work, the pH-dependent steady state kinetics for wild-type MDO and selected variants (H157N and
Y159F) are compared. Taken together with supporting EPR and Mössbauer spectroscopic studies, a
mechanistic model is proposed in which the ‘catalytic triad’ serves gate proton delivery to the substrate-
bound Fe-site.
Inorganic/Materials Chemistry 3B Sid. Richardson Lecture Hall 2
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 65
Synthesis of Linear and Branched Polymers Utilizing Hypervalent iodine Compound
Rajesh Kumar, Nicolay V. Tsarevsky*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Polymer Chemistry
A method for the preparation of chlorine-containing linear and branched polymers was developed in the
presence of 1-chloro-1, 2-benziodoxol-3(1H)-one (ClBIO), which served both as an initiator and a transfer
agent. ClBIO is a heterocyclic hypervalent iodine (III) compound with a labile I-Cl bond, which can be easily
cleaved homolytically upon heating or irradiation with visible or UV light. The reactive chlorine radicals
initiated the polymerization of methyl methacrylate at 80°C, yielding polymers with an Cl functionality at
the ɑ-terminus. Fast termination by coupling of the propagating radicals with Cl radicals and possibly Cl
transfer from ClBIO were responsible for the formation of low-molecular weight linear polymers with an
Cl group at the ɯ-end. When the polymerizations were carried out in the presence of divinyl compounds
(crosslinkers), highly branched polymers were produced prior to gelation. The network formation was
delayed in these systems until moderate to high monomer conversions were reached due to the
aforementioned termination and/or transfer, which limited the size of the interconnected chains and
therefore the average number of incorporated pendant vinyl groups per chain. The use of the ClBIO
initiating system proved to be an efficient one-pot route to mono- and dichlorine-capped linear or multi-
chlorinated branched polymers that could be easily further functionalized in future.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 66
Section 4
Organic/Analytical Chemistry 1 Sid W. Richardson Physical Sciences Building: Lecture Hall 4
Time Presenter Title
08:45-09:00 Jacob W. McCabe Texas A&M University – Commerce
Investigation of the Selected Transition Metal Binding Characteristics of Methanobactin from Methylosinus trichosporium OB3b
09:00-09:15 Taniya M.S.K. Pathiranage University of Texas at Dallas
Enhanced supramolecular self-assembly of P3HT by block copolymer synthesis
09:15-09:30 Parham Asgari University of Texas at Arlington
Catalytic Reductive ortho-C–H Silylation of Phenols with Traceless, Versatile Acetal Directing Groups and Synthetic Applications of Dioxasilines
09:30-09:45 Swetha Chinthala Texas A&M University – Commerce
Zn(II) And Cu(I/II) Co-Ordination to Alternative Metal Binding Peptide Using Ion Mobility - Mass Spectrometry and Fluorescence Spectroscopy Techniques
09:45-10:00 Yi Hu University of North Texas
β-Functionalized Push-Pull Dibenzoporphyrin
as Light Harvester for Dye-Sensitized Solar Cell
10:00-10:15 Shivaraj Yellappa University of North Texas
Phenothiazine sensitized photovoltaic cells: effect of co-adsorbant on cell performance
10:15-10:30 Enrique Barragan University of Texas at Arlington
Triazenes: Intermediates that Undergo Oxidation and Substitution Reactions
Organic/Analytical Chemistry 1 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 67
Investigation of the Selected Transition Metal Binding Characteristics of Methanobactin from Methylosinus trichosporium OB3b
Jacob W. McCabe, Rajpal Vangala, Laurence A. Angel*
Department of Chemistry, Texas A&M University – Commerce
E-mail: [email protected]
Category: Graduate
Division: Analytical Chemistry
The methanobactin (Mb) from Methylosinus trichosporium OB3b (1154.26 Da) is a member of a class
of metal binding peptides identified in methanotrophic bacteria. Methanobactins will selectively bind and
reduce Cu(II) to Cu(I), and mediate the acquisition of the copper cofactor for the enzyme methane
monooxygenase. Methanobactins will also bind other metal ions and mediate their solubilization and
transportation in situ. The structure of Mb consists of nine amino acids and two modified regions
containing enethiol-oxazolone rings which are the bidentate binding sites for Cu(I). However, the binding
characteristics for Ag(I), Pb(II), Co(II), Fe(III), Mn(II), Ni(II), and Zn(II) have not been determined. The goal of
this study is to compare the binding of these metals to the [Mb+Cu(I)-nH](n-1)− complex using traveling
wave ion mobility mass spectrometry (TWIMS). The arrival time distribution (ATD) for each metal
complex and free mb-OB3b was used to quantify the apparent binding affinity and measure their collision
cross-section at various pH points. In addition, collision-induced dissociation of the disulfide reduced
[Mb+M], was used to locate the binding sites of the individual metal(I/II) ions (M), and the normalized
collision energy, breakdown curve was measured to determine the relative stability of the disulfide
reduced [Mb+M] complexes. Selected mass spectrometry titration studies were repeated using
fluorescence spectroscopy to compare gas-phase and solution-phase techniques.
Organic/Analytical Chemistry 1 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 68
Enhanced supramolecular self-assembly of P3HT by block copolymer synthesis
Taniya M.S.K. Pathiranage, Michael C. Biewer and Mihaela C. Stefan*
Department of Chemistry and Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Organic/Polymer Chemistry
A diblock copolymer of poly(3-hexylthiophene) (P3HT) and methacrylates with pyrene side chains was
synthesized by Grignard metathesis polymerization (GRIM) and Initiators for Continuous Activator
Regeneration Atom Transfer Radical Polymerization (ICAR-ATRP). With ICAR-ATRP we could have
reduced the amount of copper used up to 90% compared to conventional ATRP while assuring good
incorporation of the second block maintaining narrow PDI. Pyrene, a thermotropic liquid crystalline
mesogen, was incorporated into P3HT. The composition of synthesized copolymer was determined by
1H-NMR analysis. Improved long-range ordering of polymer with unique morphological features was
observed in TMAFM images. Characterization of the thermotropic liquid crystalline behavior was
performed in a combined study with polarizing optical microscopy with heating stage and DSC. The liquid
crystalline mesophases of the copolymer appeared above the glass transition of P3HT which helps to
trigger long-range ordering of P3HT by co-crystallization after annealing above thermotropic mesophase
transitions. The effect of annealing on self-assembly and morphological changes of the block copolymer
was studied with tapping mode atomic force microscopy (TMAFM), thin film X-ray diffraction (XRD), and
UV-VIS analysis. The field effect mobility of the P3HT diblock copolymer was determined in organic field
effect transistors (OFET); Hole mobility as high as 10-2 cm2/Vs were measured.
Organic/Analytical Chemistry 1 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 69
Catalytic Reductive ortho-C–H Silylation of Phenols with Traceless, Versatile Acetal Directing Groups and Synthetic Applications of
Dioxasilines
Parham Asgari, Yuanda Hua, Thirupataiah Avullala, Junha Jeon*
Department of Chemistry and Biochemistry, University of Texas at Arlington,
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
A new, highly selective, bond functionalization strategy, achieved via relay of two transition metal catalysts
and use of traceless acetal directing groups, has been employed to provide facile formation of C–Si
bonds, and concomitant functionalization of a silicon group, in a single vessel. Specifically, this approach
involves the Ir-catalyzed hydrosilylation of inexpensive and readily available phenyl acetates, exploiting
disubstituted silyl synthons, to afford silyl acetals and Rh-catalyzed ortho-C–H silylation to provide
dioxasilines. A subsequent nucleophilic addition to silicon efficiently re-moves the acetal directing groups
and directly provides unmasked phenol products and, thus, useful functional groups at silicon achieved
in a single vessel. This traceless acetal directing group strategy for catalytic ortho-C–H silylation of
phenols was also successfully applied to preparation of multi-substituted arenes. Remarkably, a new,
formal -chloroacetyl directing group has been developed which allows catalytic reductive C–H silylation
of sterically hindered phenols. In particular, this new method permits to access to highly versatile and
nicely differentiated 1,2,3-trisubstiuted arenes that are difficult to ac-cess by other catalytic routes. We
demonstrated multiple synthetic potential of this strategy, such as aryne chemistry, Au-catalyzed direct
and sequential orthogonal cross-couplings, late-stage silylation of phenolic bioactive molecules, and
BINOL scaffolds.
Organic/Analytical Chemistry 1 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 70
Zn(II) And Cu(I/II) Co-Ordination to Alternative Metal Binding Peptide Using Ion Mobility - Mass Spectrometry and Fluorescence
Spectroscopy Techniques
Swetha Chinthala, Laurence A. Angel, PhD*
Department of Chemistry, Texas A&M University – Commerce
E-mail: [email protected]
Category: Graduate
Division: Analytical Chemistry
Methanotrophic bacteria are the prokaryotic organisms that oxidize methane to produce a small copper
chelating molecule called methanobactin (Mb) and are unique in their ability to utilize methane as sole
source of energy. The methanobactins produced by Methylosinus trichosporium (mb-OB3b), currently
characterized as modified chromopetides that bind to Cu(I) and other metals with high affinity, are
assumed to mediate copper acquisition from the environment for particulate methane monooxygenase
(pMMO) enzyme. Current research involves study of Cu(I/II) and Zn(II) binding to alternative metal binding
peptide with sequence CH3CO-His1-Cys2-Gly3-Pro4-Tyr5-His6-Cys7-NH2 (amb5B, MW-856.99 Da) as a function of
pH and Zn(II), Cu(I/II) concentration using fluorescence and ion mobility- mass spectrometry techniques.
Structural importance of disulfide linkage and metal binding profile of analog methanobactin will be studied.
Collision induced dissociation (CID) experiments will be conducted to induce fragmentation of peptide ions
in gas phase using mass spectrometry. A binding profile of the analog methanobactin with metal ions like
Zn (II) and Cu (I/II) will be developed in comparison to fluorescence spectroscopy.
Organic/Analytical Chemistry 1 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 71
β-Functionalized Push-Pull Dibenzoporphyrin as Light Harvester for
Dye-Sensitized Solar Cell
Yi Hu, Shivaraj Yellappa, R. G. Waruna Jinadasa, D’souz Francis*, and Hong Wang*
Chemistry Department, University of North Texas,
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Dye-sensitized solar cells (DSSC) have attracted much attention as a promising alternative to
siliconbased solar cells. [1] when it comes to photosensitizing pigments, porphyrins are obvious
candidates because of their well-known role as light harvesters and charge separations in natural
photosynthetic system. [2] In order to utilize porphyrin as DSSC sensitizer, it is very important to rationally
modify the basic porphyrin structure to maximize the light-harvesting ability, such as introduction of a
push-pull structure and elongation of porphyrin π-conjugation. [2]
Previously, we have investigated the effect of the π-conjugated spacer on the performance of DSSCs. [3]
Based on the previous results, a series of new β-functionalized push-pull porphyrin dyes were synthesized
using heck cascade reaction and bromination chemistry. In this series, the porphyrin dye with vinylene
linker substituted dibenzoporphyrin achieved the highest power conversion efficiency of 5.9 % with
highest JSC (13.80 mA), FF (0.66) and VOC (0.65 V) values. DFT calculation demonstrated a significant
shift of LUMO towards the pull group, which would help to facilitate the electron injection from photo
excited dye to the TiO2.
[1] Li, Lu-Lin, and Eric Wei-Guang Diau, Chem. Soc. Rev., 2013, 42, 291-304
[2] Higashino, Tomohiro, and Hiroshi Imahori, Dalton Trans., 2015, 44, 448-463
[3] Jinadasa, R. G., et al., ChemSusChem, 2016, 9, 2239-2249.
Organic/Analytical Chemistry 1 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 72
Phenothiazine sensitized photovoltaic cells: effect of co-adsorbant on cell performance
Shivaraj Yellappa1,2, Whitney Webre1, Habtom B. Gobeze1, Anna Middleton1, Francis D’Souza1*
1Department of Chemistry, University of North Texas, 2Government Science College, Bengaluru -560001, Karnataka, India
E-mail: [email protected]
Category: Graduate
Division: Analytical Chemistry
In this study, the co-adsorbant molecule chenodeoxycholic acid (CDCA) have a complementary effect in
the light harvest and the performance of a phenothiazine based Dye Sensitized solar cell is reported.
CDCA is used to prevent agglomeration during the soaking process onto TiO2 surface. Absorption and
fluorescence studies were performed to characterize and observe spectral coverage of the
phenothiazine dyes, whereas electrochemical studies allowed estimation of the free energy of charge
injection. B3LYP/6-31G* studies were performed to visualize location of the Frontier orbitals and their
contribution to the charge injection when they were surface modified on TiO2. Better dye regeneration
efficiency for co-adsorbed cells compared to the cells with no co-adsorbent was revealed. The kinetics of
charge injection and charge recombination on the TiO2∕phenothiazine dyes/co-adsorbent electrodes
were analysed by Femtosecond transient absorption studies. The DSSCs were built on nanocrystalline
TiO2 using the traditional two-electrode Grätzel solar cell setup with a reference cell based on N719 for
comparison purposes.
KEYWORDS: Phenothiazine dyes, organic solar cell, co-adsorbant, photoelectrochemistry; Energy
Conversion and Storage.
Organic/Analytical Chemistry 1 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 73
Triazenes: Intermediates that Undergo Oxidation and Substitution Reactions
Enrique Barragan, Alejandro Bugarin*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Molecules able to produce a variety of different synthetic targets, so-called “versatile molecules” are a
main goal in current organic chemistry research. -conjugated triazenes derived from organic azides
and N-heterocyclic carbenes are largely unexplored species. In this work, we report novel reactivity for
-conjugated triazenes. By treating these molecules in DMSO under acidic conditions, oxidation to the
corresponding aldehyde or ketone was achieved, a development compared to common methods that
require basic conditions. Additionally, by varying the reaction conditions and utilizing different O and S
nucleophiles, the corresponding ether and sulfide substitution products were obtained. These results
demonstrate that conjugated triazenes are versatile molecules that allow the use of organic azides
as synthetic scaffolds for the synthesis of aldehydes, ketones, ethers and sulfides under mild conditions
and without addition of metal catalysts.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 74
Section 4
Organic/Analytical Chemistry 2 Sid W. Richardson Physical Sciences Building: Lecture Hall 4
Time Presenter Title
11:00 -11:15 Nimmy Mammoottil University of Texas at Dallas
Surface Re-organization and Vapor Sensitivity of PNOC
11:15-11:30 Thirupataiah Avullala University of Texas at Arlington
Hydrogenative and Dehydrogenative C–C -bond silylation via a traceless directing group approach using silyl acetals
11:30-11:45 Stephen M. Budy Southern Methodist University
Microwave-assisted polyarylene: Synthesis, characterization, and optimization
11:45-12:00 Gayan A. Appuhamillage University of Texas at Dallas
3D Printable Diels-Alder Polymers as Electrical Insulating Materials
12:00-12:15 Shuai Shao University of North Texas
Self-assembled supramolecular BODIPY derived donor-acceptor systems for electron transfer
12:15-12:30 Luke Ryan Southern Methodist University
Synthesis and Characterization of Photocaged Cheiluminescent Molecules
Organic/Analytical Chemistry 2 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 75
Surface Re-organization and Vapor Sensitivity of PNOC
Nimmy Mammoottil, Bruce M. Novak*
Department of Chemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Polycarbodiimides, a class of helical macromolecules, were initially synthesized in 1994 in a living fashion.
Since then, studies on the nitrogen-rich polymer has accelerated with the discovery of the polymers’
regioregular backbone, chiroptical switching abilities, antibacterial properties and self-assembly
behaviors. Herein, poly(N-1-naphthyl-N’-octadecyl-carbodiimide) (PNOC) was synthesized and behaviors
analyzed, related to the bi-stable contraction and expansion of the helical backbone, where the sterically
bulky naphthyl group is relegated to the imine position and the octadecyl chain fixed to the amine position.
Due to PNOC’s heightened sensitivity to various organic solvents, a thin film of the polymer can be utilized
to detect miniscule differences as the film is exposed to various solvents in their vapor phase. The same
sensitivity can also be used to monitor unique surface re-organization behavior as the thin film of the
polymer experiences the contraction and expansion of the helix with the deposition of chiral solvents.
Real-time FTIR, VCD, Specific optical rotation and Goniometer studies were employed in order to quantify
the unique phenome exhibited by PNOC.
Organic/Analytical Chemistry 2 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 76
Hydrogenative and Dehydrogenative C–C -bond silylation via a
traceless directing group approach using silyl acetals
Thirupataiah Avullala, Yuanda Hua, Parham Asgari, Apparao Bokka, and Junha Jeon*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
The development of highly selective C–C -bond hydrosilylation and dehydrogenative silylation of
cyclopropanes with silyl acetal directing group is described. Specifically, cyclopropane system possessing
silyl acetal directing group would effect directed C–C-bond activation/silyl insertion over proximal Csp2–H
and Csp3–H bonds. In this work, we described the relay of Ir-catalyzed hydrosilylation of inexpensive and
readily prepared cyclopropanoacetates which we prepared by Kulinkovich reaction, followed by Rh-
catalyzed hydrogenative and dehydrogenative C–C bond silylation to provide dioxasilepines and
dioxasilolanes via putative [6,4]-bicyclic fused cyclometallated intermediate. Subsequent dehydrogenative
β-hydride elimination followed by reductive elimination would furnish dioxasilepines. Alternatively, in the
presence of Rh-Tp catalyst observed hydrosilylative sequential reductive elimination to provide
dioxasilolanes. We gained mechanistic insights into the two distinctive organocmetallic pathways. We
applied the hydrogenative and dehydrogenative C–C -bond silylation method on complex bioactive
molecules such as estradiol.
Organic/Analytical Chemistry 2 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 77
Microwave-assisted polyarylene: Synthesis, characterization, and optimization
Stephen M. Budy, Xu Chang, David Y. Son*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
A series of Diels–Alder polyarylene polymers were synthesized via microwave-assisted step-growth
polymerization. Optimization of 1,4-bis(2,4,5-triphenylcyclopentadienone)benzene with 1,4-
diethynylbenzene using a variety of solvents, concentration, and time was achieved. The polyarylene
polymers were characterized by 1H NMR, FTIR, TGA, DSC, DMA, and GPC. Thermal analysis showed little
change in the series of polymers for onset of decomposition (Td = 550 °C). Polar solvents (e.g.,
tetrahydrofuran and nitrobenzene) worked well for microwave-assisted polymerization, however,
nonpolar/aromatic solvents (e.g., toluene and xylene) also afforded lower molecular weight polyarylene
polymers/oligomers. Molecular weights were monitored over time affording well over 100 kg/mol and
dispersities more difficult to control in the range 1.9 to 20.1. Further work will involve scaling up the
polymerization reactions and also using a variety of different monomers.
Organic/Analytical Chemistry 2 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 78
3D Printable Diels-Alder Polymers as Electrical Insulating Materials
Gayan A. Appuhamillage, Grant Sturgeon, Ronald A. Smaldone*
Department of Chemistry & Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Electrical insulating materials are of great importance in wiring boards, ceramic packages, and
electronic components. Here we report a novel 3D printable insulating polymer series synthesized based
on furan and maleimide Diels-Alder chemistry containing polyether, amide, and ester functionalities in
the backbone. These functionalities govern the electrical insulating properties while the reversible Diels-
Alder dynamics of furan and maleimide moieties enable 3D printability of the material to the desired
geometry. Followed by the synthesis, these polymers were subjected to structural, thermal, and
electrical characterization. Thermogravimetric analysis (TGA) shows their high thermal stabilities up to
~ 400 °C while differential scanning calorimetry (DSC) results indicate the Diels-Alder reversibility via
endothermic transitions ~ 120-150 °C. Dielectric constant, dielectric strength, and current-voltage (CV)
measurements confirm their potential use as electrical insulating materials especially in capacitors as
high dielectric materials to enhance the capacitance, preventing current leakages in batteries and
flexible electronics.
Organic/Analytical Chemistry 2 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 79
Self-assembled supramolecular BODIPY derived donor-acceptor systems for electron transfer
Shuai Shao, Habtom Gobeze, Dr. Francis D’Souza*
Department of Chemistry, University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
A new series of self-assembled supramolecular donor–acceptor conjugates capable of wide-band
capture and exhibiting photoinduced charge separation have been designed, synthesized and
characterized using various techniques as artificial photosynthetic mimics. The donor host systems
comprise of a 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) containing a crown ether entity at the
meso-position and two styryl entities on the pyrrole rings. The styryl end groups also carried additional
donor (triphenylamine, phenothiazine, phenylferrocene) entities. The acceptor host system was a
fulleropyrrolidine comprised of an ethylammonium cation. Owing to the presence of extended conjugation
and multiple chromophore entities, the BODIPY host revealed absorbance and emission well into the
near-IR region covering the 300–850 nm spectral range. The donor–acceptor conjugates formed by
crown ether–alkyl ammonium cation binding of the host–guest system were characterized by optical
absorbance and emission, computational, and electrochemical techniques. Spectral evidence for the
occurrence of photoinduced charge separation in these conjugates was established from femtosecond
transient absorption studies. The measured rates indicated ultrafast charge separation and relatively
slow charge recombination revealing their usefulness in light-energy harvesting and optoelectronic
device applications.
Organic/Analytical Chemistry 2 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 80
Synthesis and Characterization of Photocaged Cheiluminescent Molecules
Luke Ryan, Alexander Lippert*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Chemiluminescent probes are popular synthetic targets due to their inherently high signal-to-noise ratio.
However, most chemiluminescent probes suffer from inadequate overall signal strength due to low
accumulation in the cell before the probes react. Photocaged molecules solve this problem by “caging”
the reactive site of the probe, allowing it to bioaccumulate in the cell. Here, we describe the synthesis of
several photocaged chemiluminescent molecules with tunable excitation and emission wavelengths to
achieve a chemical “color palette” of probes. Two such probes have been characterized, and exhibit both
high turn-on and wavelength excitation specificity.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 81
Section 4
Organic/Analytical Chemistry 3 Sid W. Richardson Physical Sciences Building: Lecture Hall 4
Time Presenter Title
01:30 -01:45 Ravi P. Singh University of Texas at Arlington
Studies towards the Total Synthesis of Spirocalcaridines
01:45-02:00 Apsara K. Herath University of Texas at Arlington
Approaches Toward the Total Synthesis of Nagelamides A and C
02:00-02:15 Pawan Thapa University of Texas at Arlington
Green Synthesis of Organic Dyes by Artificial Riboflavin Mimics
02:15-02:30 Hiep Nguyen University of Texas at Arlington
3,3’-of Functionalization of BINOL
02:30-02:45 Habtom B. Gobeze University of North Texas
Efficient mimicry of photosynthetic antenna-reaction center in supramolecular assemblies featuring BODIPY-Al(TTP) axially coordinated to pyridyl appended fulleropyrrolidine.
02:45-03:00 Apparao Bokka University of Texas at Arlington
Grubbs-Type Ruthenium Complex-Catalyzed Alkene-Silane Cross-Couplings and Their Synthetic Applications
Organic/Analytical Chemistry 3 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 82
Studies towards the Total Synthesis of Spirocalcaridines
Ravi P. Singh, Carl J. Lovely*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
A concise strategy towards a total synthesis of the natural products belonging to the Leucetta family of
alkaloids, spirocalcaridine A (3) and spirocalcaridine-B (4) will be described. We have developed a tandem
oxidative amination dearomatizing spirocyclization (TOADS) reaction of propargyl guanidines for the
construction of the main framework of spirocalcaridines (2) with good yields. A similar approach with
propargylic ureas resulted in the formation of 2-iminooxazoles (6) with moderate yields. We wanted to
explore the similar cyclization reaction with corresponding thioureas, but attempts to synthesize the
thioureas by reacting the propargylic amines with isothiocyanates in presence of Et3N were
unsuccessful. However, we discovered a new reaction of propargylic amines with isothiocyanates in
presence of Et3N to form 2 iminothiazoles (5) in excellent yields.
Organic/Analytical Chemistry 3 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 83
Approaches Toward the Total Synthesis of Nagelamides A and C
Apsara K. Herath, Manoj Bhandari and Carl Lovely*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Nagelamides are pyrrole-imidazole alkaloids, isolated from a marine sponge, Agelas sp. Our lab is
following a divergent strategy to synthesize several family members of these heterocyclic natural
products. Construction of scaffold A by a Stille cross-coupling reaction is the key step in the synthesis.
According to our results we found that the nitrogen atoms installation in the allylic chains is challenging
and several approaches have been utilized to introduce this feature. The current approach consists of
synthesis of allylic azides followed by acylation from thioacids and this presentation will describe this
attempt in detail.
A similar strategy can be used for the nagelamide A as well.
Organic/Analytical Chemistry 3 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 84
Green Synthesis of Organic Dyes by Artificial Riboflavin Mimics
Pawan Thapa, Frank W. Foss Jr.*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
In nature, riboflavin (Vitamin B2) is known to catalyze carbon-carbon (C-C) bond forming reactions, which
generate valuable metabolites require for proper growth, development, and survival of organisms. To
perform C-C bond formation in a sustainable manner, several artificial riboflavin mimics were designed,
synthesized, and studied to perform reactions normally carried out by heavy metals, rare-earth metals,
or powerful acids. A subclass of riboflavin mimics was found to catalyze C-C bond formation by activating
small molecules in a new manner. This approach was used to synthesize various industrially important
dyes and chemical reagents. Additionally, the relationship discovered between molecular structure and
catalytic function of riboflavin mimics in these new chemical reactions revealed a plausible explanation
for the function of natural riboflavin-dependent oxynitrilase enzymes in natural system. Oxynitrilases are
poorly understood, but valuable enzymes for the synthesis of cyanohydrins, an important class of organic
compounds. Future efforts will be aimed at the preparation of cyanohydrins and other fine chemicals
through similar green chemical methods.
Keywords: Green Chemistry, riboflavin, enzyme mimics, dyes, oxynitrilase.
Organic/Analytical Chemistry 3 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 85
3,3’-of Functionalization of BINOL
Hiep Nguyen, Yuanda Hua, Parham Asgari, Junha Jeon*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
BINOL and BINAP derivatives have facilitated an enormous set of stereoselective reactions including
various methods of carbon-carbon bond formation and catalytic heteroatom-transfer. In this talk, the
progress toward design and application of catalytic reductive ortho-C–H bond silylation with silyl acetals,
as traceless directing groups, for synthesis of a new class of 3,3’ bis-substituted BINOLs will be
presented. In detail, efficient syntheses of the 3,3’ bis-substituted BINOLs is achieved through from
dioxasilines, generated by a one-pot Ir-catalyzed ester hydrosilylation catalyzed with dialkyldihydrosilanes
and reductive Rh-catalyzed ortho-C–H silylation, by exploiting nucleophilic ring-opening addition with a
series of nucleophiles (e.g., Grignards reagents, organolithium reagents, and oxygen nucleophiles) as
well as arylation by Hiyama-Denmark cross-coupling. Moreover, the 3,3’ bis-silyl BINOLs can also be
triflated and subsequently subjected to the Au-catalyzed direct arylation to form a class of triflated 3,3’-
bis-aryl BINOLs, which can be further elaborated to 3,3’-functionalized BINAPs through the Ni-catalyzed
cross-coupling conditions.
Organic/Analytical Chemistry 3 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 86
Efficient mimicry of photosynthetic antenna-reaction center in supramolecular assemblies featuring BODIPY-Al(TTP) axially
coordinated to pyridyl appended fulleropyrrolidine
Habtom B. Gobeze,a Anthi Bagaki,b Georgios Charalambidis,b Asterios Charisiadis,b Christina Stangel,b
Vasilis Nikolaou,b Nikos Tagmatarchis,c,* Francis D’Souza,a,* Athanasios G. Coutsolelosb,*
aDepartment of Chemistry, University of North Texas, bDepartment of Chemistry, University of Crete, Laboratory of Bioinorganic Chemistry, Voutes Campus, 70013 Heraklion, Crete, Greece, cTheoretical
and Physical Chemistry Institute, National Hellenic Research Foundation; 48 Vassileos Contantinou Avenue, Athens 11635, Greece.
E-mail: [email protected]
Category: Graduate Division: Analytical Chemistry
A series of new aluminum porphyrin based dyads bearing boron dipyromethene as an excitation energy/
secondary electron donor are synthesized. In order to study the effect of orientation of the energy donor
on the rate of energy transfer different linkers are used affording BDP-O-AlTPP and BDP-COO-AlTPP.
Moreover, these dyads were axially assembled with fullerene derivatives appended with pyridyl unit for
axial coordination to the aluminum center to study photoinduced electron transfer initiated from
aluminum porphyrin to fullerene (C60). The four studied triads (BDP-COO-AlTPP-C60-pyr, BDP-COO-AlTPP-
C60-PPV-pyr, BDP-COO-AlTPP-C60-PPV-pyr and BDP-O-AlTPP-C60-PPV-pyr) are shown in Figure 1. The optical
properties of the synthesized compounds were studied using steady state UV-Vis absorption and
fluorescence techniques. The excited state lifetimes were evaluated by time correlated single photon
counting method. The studied dyads BDP-O-AlTPP and BDP-COO-AlTPP exhibited ultrafast orientation
dependent efficient excitation energy transfer mimicking the antenna system of natural photosynthesis.
Electrochemical studies were performed to determine the feasibility of excited electron transfer from
aluminum porphyrin to the electron acceptor fullerene. Subsequently, femtosecond transient absorption
with a pulse excitation of 100 fs was used to study the occurrence of photoinduced electron transfer in
the triads. The studied triads exhibited ultrafast electron transfer initiated from 1AlTPP* to generate
BDP-AlTPP•+-C60•–. The charge separated states persisted for several nanoseconds prior returning to the
ground state.
Fig. 1 Molecular structure of studied triads.
Organic/Analytical Chemistry 3 Sid. Richardson Lecture Hall 4
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 87
Grubbs-Type Ruthenium Complex-Catalyzed Alkene-Silane Cross-
Couplings and Their Synthetic Applications
Apparao Bokka, Yuanda Hua, Adam S. Berlin, Junha Jeon*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Grubbs-type ruthenium-complex-mediated intramolecular alkene hydrosilylation of alkenylsilyl ethers has
been developed to provide cyclic silyl ethers with high regioselectivity. This non-metathetical use of such
ruthenium complexes for alkene hydrosilylation via preferential Si− H bond activation over alkene
activation is notable, where the competing alkene metathesis dimerization was not detected. In addition
to the synthesis of organosilicon heterocycles from readily available olefins, this study provides
fundamental mechanistic insights into the non-metathetical function of Grubbs-type ruthenium catalysts.
In the initial stage of hydrosilylation within a ruthenium coordination sphere, evidence for activation of a
ruthenium complex by direct σ -bond metathesis between Si− H and Ru− Cl via a four-centered transition
state is presented. This study counters the traditionally accepted Chauvin-type mechanism, specifi cally
the addition of R3 Si− H across the π -bond of a Ru-benzylidene.
We have also developed regio- and stereoselective dehydrogenative silylation and hydrosilylation of
vinylarenes with alkoxysilanes, catalyzed by ruthenium alkylidenes. Varying L- and X-type ligands on
ruthenium alkylidenes permits selective access to either (E )-vinylsilanesor β -alkylsilanes with high regio-
and stereocontrol. cis,cis -1,5-Cyclooctadiene was identifi ed as the most eff ective sacrificial hydrogen
acceptor for the dehydrogenative silylation of vinylarenes, which allows use of a nearly equimolar ratio of
alkenes and silanes.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 88
Section 5
Organic/Biochemistry 1 Sid W. Richardson Physical Sciences Building: SWR 446
Time Presenter Title
08:45-09:00 Jason B. Miller UT Southwestern Medical Center
The Design and Synthesis of Zwitterionic Amino Lipids for RNA Delivery and CRISPR Gene Editing
09:00-09:15 Lindsay Davis University of Texas at Arlington
Probing the active site of F420-dependent Glucose-6-Phosphate Dehydrogenase using steady-state and pre steady-state kinetic analysis
09:15-09:30 Jian Cao Southern Methodist University
Reaction-based Chemiluminescent Agents for in vivo Imaging
09:30-09:45 Noonikara Poyil University of Texas at Arlington
Large scale synthesis of Oligoanilines
09:45-10:00 Olatunji Ojo University of Texas at Arlington
General Approach Towards Linear (E) Allylic Compounds
10:00-10:15 Aditi Nagar Southern Methodist University
Efficient synthesis of circadian clock modulator: Delta Carbolines
10:15-10:30 Sulihat Mudasiru Texas A&M University – Commerce
Enantioselective Recognition of Chiral Porphyrins Diamino-1, 1-Binapthalene Hybrids
Organic/Biochemistry 1 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 89
The Design and Synthesis of Zwitterionic Amino Lipids for RNA Delivery and CRISPR Gene Editing
Jason B. Miller1,2, Shuyuan Zhang3,4, Petra Kos1,2, Hu Xiong1,2, Kejin Zhou1,2, Sofya S. Perelman5,
Hao Zhu3,4, and Daniel J. Siegwart1,2*
1Department of Biochemistry,
2Simmons Comprehensive Cancer Center, UT Southwestern Medical Center.
3Children’s Research Institute,
4Departments of Pediatrics and Internal Medicine,
5Department of Microbiology, UT Southwestern Medical Center.
E-mail: [email protected]
Category: Graduate
Division: Biochemistry
CRISPR is a revolutionary gene editing technology with wide-ranging utility. To date, CRISPR delivery has
largely been accomplished using viruses, which have limited translational potential. The safe, non-viral
delivery of CRISPR components would greatly improve future therapeutic utility. We report the synthesis
and development of zwitterionic amino lipids (ZALs) that are uniquely able to (co)deliver long RNAs
including Cas9 mRNA and sgRNAs. A modular combinatorial synthetic design enabled rapid exploration
of a wide chemical space and the identification of a potent carrier, ZA3-Ep10. ZAL nanoparticle (ZNP)
delivery of low sgRNA doses (15 nm) reduces protein expression by > 90 % in cells. In contrast to
transient therapies (e.g. RNAi), we show that ZNP delivery of sgRNA enables permanent DNA editing
with an indefinitely sustained 95% decrease in protein expression. ZNP delivery of mRNA results in high
protein expression at low doses in vitro (< 600 pM) and in vivo (1 mg/kg). Intravenous co- delivery of
Cas9 mRNA and sgLoxP induced expression of floxed tdTomato in the liver, kidneys, and lungs of
engineered mice. The development of ZNPs provide a chemical guide for future rational design of long
RNA carriers, and represents a promising step towards improving the utility of gene editing.
Organic/Biochemistry 1 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 90
Probing the active site of F420-dependent Glucose-6-Phosphate Dehydrogenase using steady-state and pre steady-state kinetic
analysis
Lindsay Davis1, Mercy A. Oyugi1, Ghader Bashiri2,3, Edward N. Baker2,3 Kayunta Johnson-Winters1*
1Department of Chemistry and Biochemistry, University of Texas at Arlington,
2Structural Biology Laboratory, School of Biological Sciences, The University of Auckland,
Auckland, New Zealand,
3Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The
University of Auckland, Auckland, New Zealand
E-mail: [email protected]
Category: Graduate
Division: Biochemistry
F420-dependent Glucose-6-Phosphate Dehydrogenase (FGD) is an essential enzyme found with
Mycobacteria tuberculosis, the causative agent of TB disease. FGD catalyzes the conversion of Glucose-
6-Phosphate (G6P) to 6-Phosphogluconolactone, using a unique cofactor known as F420. This reaction is
carried out as the first step of the Pentose Phosphate Pathway, which is important for nucleic acid
biosynthesis. A previous crystal structure of wild-type FGD led to a proposed mechanism, suggesting
that the active site residue His40 serves as the active site base, while Glu109 serves as the acid. Our
recent work has suggested that Glu109 is the active site acid. However, His40 does not serve as the
base. The goal of this present work is to determine which amino acid could possibly serve as the active
site base, using steady state and pre-steady state kinetic experiments as well as binding.
Organic/Biochemistry 1 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 91
Reaction-based Chemiluminescent Agents for in vivo Imaging
Jian Cao, Alexander R. Lippert*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Chemiluminescence is the light emitted from a chemical reaction, and this newly generated light can be
used for detection and imaging purposes. No extra light excitation is required for the chemiluminescent
imaging, which provides a solution to the current dilemma that fluorescent probes encounter, such as
photoactivation and photobleaching. 1,2-dioxetane chemiluminescent scaffolds have been adapted by
our group for developing reaction-based imaging agents. A reactive handle is appended to this scaffold
and first reacts with the designated reactive species, followed by self-cleavage, and ultimately undergoes
a chemically initiated electron exchange luminescence (CIEEL) mechanism to produce light emission.
This design strategy has already been successfully applied for synthesizing chemiluminescent probes for
hydrogen sulfide (H2S) (CHS-3) and hypoxic conditions (HyCL-2). Those newly made probes display
instantaneous light emission upon reaction with specific reactive species that is sustained for over an
hour. Furthermore, CHS-3 and HyCL-2 have been successfully applied for H2S and tumor hypoxia imaging
in living animals using CCD camera technology. Furthermore, HyCL-3 has been made recently by
appending an acrylonitrile group into the 1,2-dioxetane scaffold, which dramatically increases
chemiluminescent emission and eliminates the use of Emerald II Enhancer (an enhancer used in our
previous study to enhance the light production). Work is being done towards developing a NIR
chemiluminescent scaffold which will open gates for deep tissure living animal imaging.
Organic/Biochemistry 1 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 92
Large scale synthesis of Oligoanilines
Noonikara Poyil, A.; Bugarin, A.*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Oligoanilines are known for its vast variety of synthetic applications. Recently, oligoanilines have attracted
considerable research attention due to their conductive and physical properties. We have developed an
efficient large scale synthetic procedure to synthesize several oligoanilines with high purity. This method
reduces the formation of byproducts and gives products with high purity. The desired oligoanilines were
synthesized using few simple steps and employing routine purification methods. We will also present
their applications in conductive elastomers.
Organic/Biochemistry 1 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 93
General Approach towards Linear (E) Allylic Compounds
Olatunji Ojo, Alejandro Bugarin*
Department of Chemistry and Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Allylic compounds are one of the most valued building blocks in synthesis. The synthesis of several allylic
acetates and its derivatives employed two-step approach from readily available starting materials. The
approach afforded high yield in a metal-free procedure, ambient reaction conditions, with the linear and
(E)–conformer as the only adduct. The reactions are tolerant to many nucleophiles such as carbon,
nitrogen, oxygen, and sulfur given a high yield product. Our future goal is to extend the scope to
phosphorus nucleophiles.
Organic/Biochemistry 1 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 94
Efficient synthesis of circadian clock modulator: Delta Carbolines
Aditi Nagar, Edward. R. Biehl, Brian D. Zoltowski*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Cryptochrome (CRY) is an important class of mammalian flavoprotein, which participates in various
metabolic pathways including sleep-wake cycle, hormone secretion in an auto-regulatory manner.
Biochemical studies have shown its involvement in regulating hepatic gluconeogenesis, hence, could be
a potential diabetes target. Recently, carbazole scaffolds have been demonstrated to bind the active site
of cryptochrome, however, it lacks critical H-bonding that can facilitate recognition and binding. In
contrast, carbolines, which contain two fused nitrogen rings, are important class of pyrido-indole
derivatives that could potentially introduce H-bonding characteristics to the carbazole scaffold. Notably,
these carboline scaffolds have been targeted as potential drug molecules. Specifically, beta-carbolines
occur widely in nature and have been studied as potential anti-cancer and anti-malarial
compounds. Delta-carbolines are less common in nature and historically been viewed as having cytotoxic
effects. To better understand the functional differences of carbazole, delta-carboline and beta-carboline
scaffolds we sought out to prepare analogs varying in the core scaffold. In the process, we have identified
two-step robust formation of delta-carbolines via reactions of benzyne and 2-halo-aminopyridines,
followed by microwave intramolecular cyclization.
Organic/Biochemistry 1 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 95
Enantioselective Recognition of Chiral Porphyrins Diamino-1, 1-Binapthalene Hybrids
Sulihat Mudasiru, Stephen Starnes*
Department of Chemistry, Texas A&M University – Commerce
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Biological molecules such as proteins exist as chirally pure single enantiomers which selectively
recognize chiral substrates or selectively catalyze the biosynthesis of single enantiomer chiral products.
This project aims to mimic biological molecules in the body. In this report, host complexes consisting of
tetraphenylporphyrins (TTP) diamino-1,1-binapthalene were synthesized by attaching (S)-(-) 2, 2-diamino-
1,1-binapthalene and (R)-(+)-2,2-diamino-1,1-binapthalene to TTP isocyanate in order to improve the
selectivity of this host in its chiral guest binding properties, with the ultimate goal of studying affinities of
host to the guests. Chiral guests studied were L-nicotine, R and S mandelate, and D-n-acetyl and L-n-
acetyl phenylalanine. Proton NMR, Mass spectrometry, UV-Vis and CD spectroscopy were used to
characterize the compounds and study their chiral host-guest binding properties. We proposed that R-
guests will bind selectively with R-TTP host molecules while S-guest will bind preferentially to S-TTP
molecules. L-Nicotine was found to show moderate selectivity with the S-TTP complex compared to other
guests studied that showed little to no selectivity in the host-guest complex. Future work will focus on
synthesizing new host-guest complexes and studying their chiral recognition properties.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 96
Section 5
Organic/Biochemistry 2 Sid W. Richardson Physical Sciences Building: SWR 446
Time Presenter Title
11:00 -11:15 Maha Aljowni Southern Methodist University
Synthesis of anti-cancer drugs to inhibit P-gp pumping action
11:15-11:30 Sampath B. Alahakoon University of Texas at Dallas
Improved Structural Arrangement in 2D Azine-linked Covalent Organic Frameworks upon Fluorination
11:30-11:45 Udaya Sree Dakarapu University of Texas at Arlington
Lewis Base Activation of Silyl Acetals: Iridium-Catalyzed Reductive Horner-Wadsworth-Emmons Olefination
11:45-12:00 Lawton A. Seal II University of Texas at Arlington
Studies Toward the Total Synthesis of (-)-Spiroleucettadine
12:00-12:15 Jayendra Chunduru Texas A&M University – Commerce
Isolation of a Pyrimidine Biosynthetic Pathway Mutant in Pseudomonas monteilii
12:15-12:30 Robert Green Southern Methodist University
Oxidative stress sensing mechanisms in ZEITLUPE
Organic/Biochemistry 2 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 97
Synthesis of anti-cancer drugs to inhibit P-gp pumping action
Maha Aljowni, Alexander Lippert*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
In recent years, many cancer chemotherapeutic agents have not shown much promise because they
have failed to accumulate in cancer cells long enough to have any effect. This is due to the overexpression
of a plasma membrane protein called P-glycoprotein (P-gp). Generally, the role of P-gp is to protect the
cells from any toxins or foreign substances by pumping these toxins (including chemotherapeutic drugs)
out of the cell. As part of my graduate research, biologists at SMU are using a computer-generated
model to predict the structures of P-gp inhibitors that can be synthesized in order to stop or inhibit the
action of P-gp. This model is proposed to help researchers stop P-gp pumping after docking with new
drugs and to understand the mechanism of it. Furthermore, my current research is focused on a
collaboration with the chemistry and biology departments for synthesizing multiple drug analogues that
can inhibit the P-gp protein. These are being tested in cancer cell lines for efficacy and strength of
inhibition so that future chemotherapeutic drugs can work effectively in cells.
Organic/Biochemistry 2 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 98
Improved Structural Arrangement in 2D Azine-linked Covalent Organic Frameworks upon Fluorination
Sampath B. Alahakoon, Gregory T. McCandless, Arosha A. K. Karunathilake, Christina M.
Thompson, Ronald A. Smaldone*
Department of Chemistry & Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Here, we report a structural analysis of a series of azine-liked 2D covalent organic frameworks (COFs)
synthesized utilizing two novel fluorinated monomers to their non-fluorinated equivalent. We found that
the fluorinated monomers could produce 2D-COFs with enhanced material properties. The fluorinated
COFs displayed BET surface areas over 2000 m2 g−1 compared to the non-fluorinated COF (760 m2 g−1).
And also, displayed more well-defined meso-pores with improved crystallinity. To get a greater insight to
the mechanism of formation, we studied the COF formation under varying reaction times and
temperatures.
Organic/Biochemistry 2 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 99
Lewis Base Activation of Silyl Acetals: Iridium-Catalyzed Reductive Horner-Wadsworth-Emmons Olefination
Udaya Sree Dakarapu, Apparao Bokka, Parham Asgari, Gabriela Trog, Yuanda Hua, Hiep H
Nguyen, Nawal Rahman, Junha Jeon*
Department of Chemistry & Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Homologation of esters to α ,β -unsaturated esters is a useful transformation in organic synthesis. We
have developed a new approach for the Ir-catalyzed reductive Horner-Wadsworth-Emmons olefination of
esters; a one-pot method for the transformation of esters to α ,β -unsaturated esters utilizing silyl acetals
as aldehyde equivalents followed by Horner-Wadsworth-Emmons olefination. Lewis based activation of
silyl acetals formed by Ir-catalyzed hydrosilylation of esters initially generates putative penta-coordinate
silicate acetals which fragment into aldehydes, silanes and alkoxides in situ . The alkoxides deprotonate
phosphonate esters which subsequently react with the aldehydes to furnish α ,β -unsaturated esters.
Resulting α ,β -unsaturated esters are subsequently reduced chemoselectively. This method is
operationally simple compared with aluminium hydride-based reductive Horner-Wadsworth-Emmons
olefination. Notably, Horner-Wadsworth-Emmons olefination of traditionally challenging substrates such
as aryl, alkenyl and alkynl esters furnishes the corresponding α ,β - unsaturated esters at room
temperature with excellent stereoselectivities (E/Z > 20:1) and moderate to excellent yields (48–91%).
This transformation will contribute to enhancing the utility of silyl acetals in synthetic chemistry.
Organic/Biochemistry 2 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 100
Studies Toward the Total Synthesis of (-)-Spiroleucettadine
Lawton A. Seal II, Carl Lovely*
Department of Chemistry & Biochemistry, University of Texas-Arlington
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Total synthesis of natural products can lead to the innovation of new reactions, support or refute
proposed structural assignments of the isolated natural product, and provide sizable quantities suitable
for testing the biological activity of the compound. Our lab has devised a route for the total synthesis
spiroleucettadine, that not only would accomplish all three of the aforementioned scientific objectives,
but also, if successful, this would be the first reported total synthesis of this molecule. Our strategy was
to first utilize methodological techniques to thoroughly explore the scope of a novel oxidative addition
reaction previously discovered in our lab, and attempt to utilize it in a key step of our synthesis. With the
methodology study mostly completed, total synthesis of the molecule has commenced. During this oral
discussion we will present our findings thus far with respect to the methodology and total synthesis of
spiroleucettadine.
Organic/Biochemistry 2 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 101
Isolation of a Pyrimidine Biosynthetic Pathway Mutant in Pseudomonas monteilii
Jayendra Chunduru, Thomas P. West*
Department of Chemistry, Texas A&M University – Commerce
E-mail: [email protected]
Category: Graduate
Division: Biochemistry
The isolation of a pyrimidine biosynthetic pathway mutant in Pseudomonas monteilii ATCC 700476 was
investigated. Initially, the ATCC 700476 cells were subjected to chemical mutagenesis with 1%
ethylmethane sulfonate. The mutagenized cells were next subjected to two rounds of D-cycloserine (1
mg/ml) counter selection in glucose minimal medium for 2 hours at 30oC with aeration to eliminate wild-
type cells. The surviving cells were screened for uracil auxotrophy and one uracil auxotroph was
identified. This mutant grew at 30oC on uracil, cytosine or uridine when either 0.4% glucose or succinate
was the carbon source. Also, the uracil auxotroph grew on 50 mg/l orotic acid if glucose was the carbon
source. The activities of the pyrimidine biosynthetic pathway enzymes aspartate transcarbamoylase,
dihydroorotase, dihydroorotate dehydrogenase, orotate phosphoribosyltransferase and orotidine 5’-
monophosphate decarboxylase were measured in the mutant cells grown at 30oC on glucose or
succinate minimal medium containing uracil. The activity of dihydroorotase was found to be substantially
reduced in the mutant cells whether grown on glucose or succinate as a carbon source in the uracil-
containing medium. Overall, this study demonstrates that the isolation of a pyrimidine biosynthetic
pathway mutant strain from P. monteilii ATCC 700476 is feasible using conventional mutagenesis and
selection procedures.
Organic/Biochemistry 2 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 102
Oxidative stress sensing mechanisms in ZEITLUPE
Robert Green, Brian D. Zoltowski*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Biophysics
Organisms have evolved to sense and adapt to daily and seasonal environmental ques to maximize their
fitness through biological responses. Proteins containing Light, Oxygen, or Voltage (LOV) domains act at
signaling nodes to integrate oxidative stress, metabolism and light into circadian, reproductive and
stress pathways. In plants the ZEITLUPE (ZTL) family of blue-light photoreceptors are responsible for
integrating these signals into circadian and photoperiodic responses by allosteric regulation. These
mechanisms are likely conserved in plants, fungi and mammals but are still poorly understood. To better
understand the allosteric mechanisms that allow ZTL signaling, we focused on residue G46 which is in
close proximity to Q154, a residue involved in signal transduction. Mutating this residue to S46 forces
Q154 to a buried conformation which mimics the light-state. This allows direct analysis of the light-driven
global conformational response. Using chemical, biophysical, and in vivo approaches we have identified
oxidative stress sensing mechanisms in ZTL that integrate environmental stress, light and circadian
function.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 103
Section 5
Organic/Biochemistry 3 Sid W. Richardson Physical Sciences Building: SWR 446
Time Presenter Title
01:30 -01:45 Charles Ochoa Texas Christian University
Intramolecular deMayo Photocyclization: The Total Synthesis of Hippadine and Pratosine
01:45-02:00 Caleb M. Bunton Southern Methodist University
Catalyst controlled Thiol-Michael reactions for the study of catalyst efficiency
02:00-02:15 Shital Kale Southern Methodist University
Study of blue-light photoreceptor proteins in Soybean and Brassica rapa
02:15-02:30 Marlius Castillo Texas Christian University
Small molecule fluorophores as environmental probes
02:30-02:45 Christopher O. Obondi University of North Texas
Photoinduced charge separation in wide-band capturing, multi-modular bis(donor styryl)BODIPY-fullerene systems
02:45-03:00 Adam Montoya Texas Christian University
Steps towards the Synthesis of Phenanthridone Analogs
03:00-03:15 Vishal Rajat Sharma Texas Christian University
Triazine-substituted Hydrazones as Potential Drug Delivery Analogs
Organic/Biochemistry 3 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 104
Intramolecular deMayo Photocyclization: The Total Synthesis of
Hippadine and Pratosine
Charles Ochoa, Dr. David E. Minter*
Department of Chemistry & Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Various total syntheses of the Lycorine-type pharmacologically active alkaloids hippadine and pratosine
have been developed. However, most of these synthetic routes require prohibitively expensive materials
and/or achieve yields that are subpar, making these schemes unlikely to be used in an industrial setting.
Current research involves developing better synthetic methods for these two alkaloids starting with a
6,7-disubstituted isoquinoline. These syntheses are appealing since they utilize readily available starting
materials and avoid expensive catalysts. The key step in the synthetic scheme centers around an
intramolecular de Mayo photocyclization which involves a reaction between an alkene moiety in the
isocarbostyril system and a 1,3-diketone (a functionalized tether on nitrogen), which forms a third ring
in the structure of the molecule. Research on a model system (an isocarbostyril without the substituents
at positions 6 and 7) for these natural products has been done in order to elucidate the optimal
conditions for each step on the synthetic strategy. The established synthetic strategy led to compounds
along the synthetic route that had very undesirable solubility properties. To resolve this issue, the
substituents were replaced with bulkier, more non-polar moieties in order to increase the solubility of
the compound in ethyl ether.
Organic/Biochemistry 3 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 105
Catalyst controlled Thiol-Michael reactions for the study of catalyst
efficiency
Caleb M. Bunton, David Son*
Department of Chemistry and Biochemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
The thiol-Michael addition reaction is a versatile tool that has recently found its way into the
toolbox of many chemists. Although this reaction follows a Michael addition reaction pathway,
the nucleophilic initiated thiol-Michael reaction may proceed under mild conditions, with the use
of a trace amount of catalyst, and may proceed quickly with high conversion. Ultimately the
efficiency of the nucleophilic initiated thiol-Michael addition rests solely on the nature of the
catalyst used. It is therefore important to determine the most efficient catalyst to utilize for a
specific chemical system, especially when the tuning of the properties of the final product is
desired.
In this study, a selection of amine catalysts was utilized in conjunction with multi-substituted thiol
and acrylate substrates to determine reaction efficiency in a catalytic mediated thiol-Michael
addition reaction. The efficiency of the catalytic mediated thiol-Michael reaction was determined
in terms of reaction completion rate in the presence of varying temperature, catalytic
nucleophilicity, as well as catalytic steric considerations. Increasing the efficiency of these
reactions facilitates the ability to produce a wide range of tunable designer materials at a large
scale while maintaining cost effectiveness.
Organic/Biochemistry 3 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 106
Study of blue-light photoreceptor proteins in Soybean and Brassica rapa
Shital Kale, Brian Zoltowski*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Biochemistry
Plants utilize light not only for growth and development but also to synchronize physiological process with
daily environmental changes. Arabidopsis thaliana is a useful model for plant circadian rhythms and
photoperiodic flowering. In Arabidopsis, LOV domain containing blue-light photoreceptors Zeitlupe (ZTL),
Flavin-Kelch-Fbox-1 (FKF1) and LOV-Kelch-Protein-2 (LKP2) are involved in the regulation of the circadian
clock and seasonal flowering. These plant photoreceptors contribute to agricultural productivity.
Therefore, we extended these plant photoreceptor studies to Soybean and Brassica rapa, the world’s
major agricultural crops. Sequence alignments of photoreceptor ZTL/FKF1 of Arabidopsis similar to
the Brassica rapa LKP2 families as well as Soybean ZTL/FKF1 family members. In order to understand
biological functions of Soybean and Brassica rapa, it is vital to understand its photocycle and chemical
activation. Accordingly, we studied photochemical characterization to confirm the recovery rates of
these LOV domain photoreceptors.
Organic/Biochemistry 3 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 107
Small molecule fluorophores as environmental probes
Marlius Castillo, Sergei V. Dzyuba*
Department of Chemistry & Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Fluorescence probes are notably important due to the numerous applications they have. This is the case
in BODIPY dyes which have been considered in biological and supramolecular labeling, photodynamic
therapy, material sciences and synthetic chemistry, among many others applications. Our interest in
BODIPY structures is given by its remarkable characteristics, such as high brightness and good solubility
and spectroscopy properties that can be easily tuned. It is our goal to develop BODIPY dyes that can be
used as viscosity sensors since this is one fundamental physical property in biological assemblies.
In this focus, we synthesized and studied two novel BODIPY based viscometers were through their
absorption, emission, and fluorescence lifetime in different solvents. Also, the unusual aggregation of
BODIPY fluorophores in 1,1-dichloroethane was analyzed using spectroscopy techniques. Furthermore,
we are currently investigating a porphyrin homodimer dye that might be capable of novel melting point
assessment of gels constituted of low molecular weight gelatin with molecular solvents and ionic liquids.
The applications of the presented contributions on environmental probes have the potential to help
develop and advance the analysis of biological systems between other research areas.
Organic/Biochemistry 3 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 108
Photoinduced charge separation in wide-band capturing, multi-modular
bis(donor styryl)BODIPY-fullerene systems
Christopher O. Obondi,a Gary N. Lim,a Paul A. Karr,b Vladimir N. Nesterov,a Francis D’Souzaa,*
aDepartment of Chemistry, University of North Texas
bDepartment of Physical Sciences and Mathematics, Wayne State College
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
A series of multi-modular donor-acceptor systems capable of exhibiting photoinduced charge separation
have been designed, synthesized and characterized using various techniques. In this series, the electron
donor was a BF2-chelated dipyrromethene (BODIPY) appended with two styryl linkers carrying two
electron rich triphenylamine or phenothiazine entities. Fulleropyrrolidine linked at the meso-position of
the BODIPY ring served as an electron acceptor. As a result of extended conjugation and multiple
electroactive chromophore entities, the bis-styryl BODIPY revealed absorbance and emission well-into
the near-infrared region covering 300-850 nm spectral range. Using redox, computational, absorbance
and emission data, an energy level diagram was constructed that helped in envisioning the different
photochemical events. Spectral evidence for photoinduced charge separation in these systems was
established from femtosecond and nanosecond transient absorption studies. The measured rate
constants indicated fast charge separation and relatively slow charge recombination revealing their
usefulness in light energy harvesting and optoelectronic device building applications.
Organic/Biochemistry 3 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 109
Steps towards the Synthesis of Phenanthridone Analogs
Adam Montoya, David E. Minter*
Department of Chemistry & Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
Phenanthridone-type alkaloids isolated from certain plants of the Amaryllidaceae family are of interest
due to their pharmaceutically active nature. The compounds are commonly used in research concerning
cancer, Alzheimer’s disease and other human illnesses. One of the main hindrances to such research
is the limited availability of many of these compounds. The Minter group is interested in the development
of procedures for synthesizing such alkaloids in a cost-effective and time efficient manner, while at the
same time maintaining fair to excellent yields. Techniques toward the synthesis of natural products of
the Phenanthridone type are presented herein. Manipulations were tested and optimized on a model
system in order to save both time and funds while developing a synthetic pathway to be utilized in the
formation of more complex compounds. Setbacks such as the reduction of a tetra-substituted double
bond have been encountered. However, adjustments are being made to avoid such difficulties in the
future. Ideally, the proposed scheme will ultimately allow for the synthesis of several phenanthridone
analogues.
Organic/Biochemistry 3 SWR 446
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 110
Triazine-substituted Hydrazones as Potential Drug Delivery Analogs
Vishal Rajat Sharma, Eric E. Simanek*
Department of Chemistry & Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Graduate
Division: Organic Chemistry
The hydrazone functional group has been extensively studied due to its versatile applications, simple
synthesis, and unique structural properties. Among those, the acid-labile property can be utilized to
control hydrolysis rates at different pH conditions. Here, we exploited the triazine ring system to
introduce the hydrazone groups. To improve the solubility of hydrazones in water, the chlorine atoms of
the triazine ring were substituted by bigger polar groups, aminoethoxyethanol. Thus, substituted triazine
ring system can potentially be used to deliver drugs that have poor water solubility. The hydrolysis rate
of various hydrazones were studied under different pH conditions. Furthermore, presence of different
groups (-H, -CH3, or -C6H5) on N2 of the same hydrazone show different hydrolysis rates under the same
pH conditions. Among three groups on N2, hydrazones with –CH3 hydrolyzed the fastest as its electron
donating nature makes N1 more nucleophilic. This presentation introduces different hydrazones,
including their release studies in different pH solutions, as well as future plans for incorporating drugs
in our substituted triazine-ring systems.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 111
Section 6
Physical/Computational Chemistry 1 Sid W. Richardson Physical Sciences Building: SWR 360
Time Presenter Title
08:45-09:00 Peter Niedbalski University of Texas at Dallas
Dynamic Nuclear Polarization: Boosting 13C MRI Signals by >10,000-fold
09:00-09:15 Ahmad Najafian University of North Texas
DFT Study of Methane Activation by 3d Metal Alkoxides
09:15-09:30 Erik Antonio Vázquez-Montelongo University of North Texas
Computational Investigation of Intermolecular Interactions Between Functionalized Single-walled Carbon Nanotubes and Polyethylene Terephthalate
09:30-09:45 Qing Wang University of Texas at Dallas
Hyperpolarized 89Y-EDTP and 89Y-DTPP as pH Sensitive MRI Agents
09:45-10:00 Stephanie I. Jones Texas Christian University
Acid Catalyzed Hydrolysis of Lignin Model
Compounds with β-O-4 Linkages
10:00-10:15 Riffat Parveen University of North Texas
Effect of Ancillary Ligands on Oxidative Addition of CH4 to Re(III) Complexes: A = B, Al, CH, SiH, N, P Using MP2, CCSD(T) and MCSCF Methods
10:15-10:30 Christopher Parish University of Texas at Dallas
Mechanisms of 13C Dynamic Nuclear Polarization in a Mixture of Two Free Radicals
Physical/Computational Chemistry 1 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 112
Dynamic Nuclear Polarization: Boosting 13C MRI Signals by >10,000-fold
Peter Niedbalski, Christopher Parish, Qing Wang, Lloyd Lumata*
Department of Physics, The University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Physical Chemistry
Dissolution dynamic nuclear polarization (DNP) has become a widely used technique for created highly
polarized liquid-state solutions of nuclear spins that may then be monitored using nuclear magnetic
resonance (NMR) or magnetic resonance imaging (MRI). The already-impressive signal enhancements
gained through DNP can be further enhanced by the addition of trace amounts of gadolinium or holmium
ions to the sample. Typically, these ions are chelated within a stable ligand in order to render them inert
for biomedical applications. We have investigated the use of two other ions in the lanthanide family,
dysprosium and terbium, and found that they too yield significant 13C polarization enhancement. In the
case of terbium, polarization levels similar to those achieved with gadolinium may be reached with only
a fraction of the ion concentration required of gadolinium. In addition to terbium and dysprosium, we
have explored the use of gadolinium chelated in a novel trimeric ligand, 3-Gd, and found that its
performance as a DNP additive rivals that of conventional monomeric gadolinium complexes. The
physical mechanisms as to how to achieve 13C MRI signal enhancements of >10,000-fold will be
discussed.
Physical/Computational Chemistry 1 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 113
DFT Study of Methane Activation by 3d Metal Alkoxides
Ahmad Najafian, Thomas Cundari*
Department of Chemistry, Center of Advanced Scientific Computing and Modeling (CASCaM),
University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Conversion of methane (natural gas) to methanol, an easily transportable liquid, is an important reaction
to industry. In this study, the reaction pathway and thermodynamics for methane-to-methanol conversion
by first-row transition metal methoxide complexes are evaluated using density functional theory (DFT).
Three supporting ligands with different formal charges give an opportunity to evaluate different formal
oxidation states of the metal (MI, MII, MIII) as a factor to control the C-H activation reaction, as well as the
number of d-electrons on the metal. Several interesting conclusions have been derived thus far from the
calculations. First, d-orbital occupation plays a more significant role in controlling the thermodynamics
and kinetics of the methane activation reaction than either the metal formal charge and the properties
of the supporting ligand. Second, moving toward first row late-transition metals in periodic table showed
more thermoneutral reactions for 3d metal ions with high d-counts. Third, for the earlier 3d metals
studied thus far, the reaction seems to go through a four-centered transition state via a σ-bond
metathesis mechanism, but for the later 3d metals, activation of the methane C-H bond occurs through
an oxidative hydrogen migration mechanism.
Physical/Computational Chemistry 1 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 114
Computational Investigation of Intermolecular Interactions Between Functionalized Single-walled Carbon Nanotubes and Polyethylene
Terephthalate
Erik Antonio Vázquez-Montelongo1,2, Adrián Rico-Campos3, Dalyndha Aztatzi-Pluma3,
Juan Francisco Javier Alvarado3, Edgar Omar Castrejón-González3, G. Andrés Cisneros1,2*
1 Department of Chemistry, University of North Texas, Denton.
2 Center for Advanced Scientific Computing and Modeling, University of North Texas.
3 Departamento de Ingeniería Química, Instituto Tecnológico de Celaya, Celaya, Gto. México.
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Carbon nanotubes (CNTs) have been used as reinforcing agents for polymers. However, CNTs form
stable aggregates, which make it complicated to disperse them into the polymeric matrix. A popular
method to overcome this issue is by functionalizing the CNTs with compatible chemical groups with the
polymeric matrix. Therefore, knowing the specific type of functional group and its non-covalent
interactions with a given CNT is useful to achieve a proper CNT dispersion into polymeric matrices. Non-
covalent interactions analysis (NCI) and zeroth order symmetry-adapted perturbation theory (SAPT0)
calculations were performed to study intermolecular interactions of several single-walled carbon
nanotubes (SWCNT) functionalized with carboxyl (-COOH), amine (-NH2), hydroxyl (-OH) and phenyl (-Ph)
groups, interacting with a polyethylene terephthalate (PET) chain. We identified hydrogen bonds (HBs)
between donors from the functional groups on the SWCNT (-OH, -COOH and -NH2) and acceptors
(carbonyl oxygens) on the PET chain. Additional attractive interactions were observed between the
aromatic groups in the PET polymer chain and the SWCNT (PET/SWCNT-Ph and PET/SWCNT
interfaces). Details of the intermolecular interactions calculated with NCI and SAPT will be presented.
Physical/Computational Chemistry 1 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 115
Hyperpolarized 89Y-EDTP and 89Y-DTPP as pH Sensitive MRI Agents
Qing Wang, Peter Niedbalski, Christopher Parish, and Lloyd Lumata*
Department of Physics, The University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Physical Chemistry
Nuclear magnetic resonance (NMR) is widely used for decades due to its many advantages, but plenty
of low gyromagnetic ratio nuclei are limited by their inherent insensitivity, such as 89Y. However,
dissolution dynamic nuclear polarization (DNP) has made fast acquisition of 89Y NMR spectra possible by
producing a highly polarized liquid-state sample whose signal persists for relatively long time. This
technology successfully enhanced 89Y NMR signal greater than 60,000-fold. Due to this solid signal
buildup, 89Y complexes were found that they tend to be sensitive to pH. In order to study this interesting
phenomenon, two ligands, Y-EDTP and Y-DTPP, were chosen as candidates. They were polarized and
introduced into various pH buffers solutions, followed by high resolution NMR spectroscopy on these
samples, and their chemical shift dispersion was tested. The result shows that Y-EDTP behaves very well
that the chemical shift of it is highly dependent on different pH between pH 5.7 to 9.15 but no signal is
discovered below pH 5. On the other hand, the chemical shift of Y-DTPP is almost constant between pH
7 and 9. In comparison, 89Y-EDTP have more potential to be a pH sensitive agent in hyperpolarized MRI.
Physical/Computational Chemistry 1 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 116
Acid Catalyzed Hydrolysis of Lignin Model Compounds with β-O-4
Linkages
Stephanie I. Jones, Benjamin G. Janesko*
Department of Chemistry & Biochemistry, Texas Christian University
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Lignocellulose is produced at about 170 billion metric tons annually, but lignin (a component of
lignocellulose) is a waste stream in biorefinery processes. Lignin accounts for up to 40% by energy in
lignocellulose and is a polymerization of three major phenolic components: p-coumaryl alcohol, coniferyl
alcohol and sinapyl alcohol. The ratio between these components vary in different plants, wood tissues,
and cell wall layers. Improving lignin valorization is likely important for lignocellulose-based biorefineries
for there are only a limited number of utilizations in lignin derivatives. In this study, we use computational
chemistry to study two acid-catalyzed hydrolysis mechanisms of lignin model compounds: E1 elimination
and dehydration versus protonation and nucleophilic substitution.
Physical/Computational Chemistry 1 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 117
Effect of Ancillary Ligands on Oxidative Addition of CH4 to Re(III) Complexes: A = B, Al, CH, SiH, N, P Using MP2, CCSD(T) and MCSCF
Methods
Riffat Parveen, Thomas R. Cundari*
Department of Chemistry, Center of Advanced Scientific Computing and Modeling (CASCaM),
University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
A computational study for oxidative addition of methane to Re(OC2H4)3A (where A may act as an ancillary
ligand and thus can interact with the metal) was carried out. The choice of ancillary ligands have been
made based on their electronic properties: A = B or Al (Lewis acid), CH or SiH (electron precise), N (σ-
donor) and P (σ-donor/π-acid). The main objective of this study was to understand that how variation in
A affects the structural and electronic properties of the reactant d4-Re(III) complex, which can ultimately
tune the kinetics and thermodynamic of OA. Results obtained from MP2 calculations revealed that for
OA of CH4 to Re(OC2H4)3A, the order of ΔG≠ for a choice of ancillary ligand is B > Al > SiH > CH > N > P, thus
making Re(OC2H4)3P the best candidate for OA of methane. Single point calculations for ΔG≠ obtained with
CCSD(T) showed excellent agreement with those computed with MP2 methods. MCSCF calculations
indicated that oxidative addition transition states are well described by a single electronic configuration,
giving further confidence in the MP2 approach used for geometry optimization and ΔG≠ determination,
and that the transition states are more like the d4 Re(III) reactant than the d2-Re(V) product.
Physical/Computational Chemistry 1 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 118
Mechanisms of 13C Dynamic Nuclear Polarization in a Mixture of Two Free Radicals
Christopher Parish, Peter Niedbalski, Qing Wang, Andhika Kiswandhi, Likai Song and Lloyd
Lumata*
Department of Physics, The University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Physical Chemistry
Dynamic nuclear polarization (DNP) describes the transfer of the free radicals’ high electron polarization
to the nuclei via microwave irradiation of a diamagnetic sample homogeneously distributed throughout
a glassing matrix at low temperatures and high magnetic fields. Dissolution DNP extends this high
polarization to apply to liquids. As such, the properties of the free radical(s) used may significantly impact
the DNP results. We have examined the effect of varying the wide linewidth free radical 4-Oxo-TEMPO’s
concentration while in the presence of the narrow linewidth free radical trityl OX063 at optimum
concentration. The polarization profiles and intensities were compared for different 4-Oxo-TEMPO
concentrations. This study found that, if the sample was polarized about trityl OX063’s spin-up peak,
increasing 4-Oxo-TEMPO concentrations led to the intensity maxima decreasing before plateauing;
whereas, if the sample was polarized about trityl OX063’s spin-down peak, increasing 4-Oxo-TEMPO
concentrations led to the intensity maxima increasing and passing through zero before plateauing.
Additionally, the temperature-dependent electron spin resonance (ESR) behavior and ESR spectra were
acquired. Two possible mechanisms for this DNP behavior will be discussed.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 119
Section 6
Physical/Computational Chemistry 2 Sid W. Richardson Physical Sciences Building: SWR 360
Time Presenter Title
11:00 -11:15 Feng Wang Southern Methodist University
Atomic Details of Binding Modes between Antibiotics and Bacteria Cell Wall through Molecular Dynamics Simulations
11:15-11:30 Azadeh Nazemi University of North Texas
Control of C-H Activation by Mo-Oxo Complexes: pKa or BDFE?
11:30-11:45 Susana Aguirre-Medel University of Texas at Arlington
Porous Silicon Oxycarbide (SiCO) Materials
11:45-12:00 Siying Lyu Southern Methodist University
The Role of H-bonding in DNA
12:00-12:15 Zhicheng (Daniel) Sun University of North Texas
Computational Study of C-H Activation of Methane by Diiminopyridine Nitride Complexes
12:15-12:30 Vytor Oliveira Southern Methodist University
Exploring the Nature and Strength of Chalcogen Bonding for the Rational Design of New Materials
Physical/Computational Chemistry 2 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 120
Atomic Details of Binding Modes between Antibiotics and Bacteria Cell Wall through Molecular Dynamics Simulations
Feng Wang, Hongyu Zhou, Sung Joon Kim, and Peng Tao*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Vancomycin is an antibiotic used as the first line treatment for many infections like skin and bloodstream
infections. It can inhibit the cell wall synthesis of Gram-positive bacteria through binding to the cell wall
structure. It is proposed that the vancomycin binds to a peptide chain of cell wall, and prevents the
completion of cell wall synthesis through crossing linking. Due to the limitation of experimental approach,
the atomic details of binding mode of vancomycin and the target peptide chain of cell wall structure are
yet to be obtained. To address this need, we carried out molecular dynamics (MD) simulation of the
systems of vancomycin bound with S.aureus peptidoglycan unit. We also carried out similar MD
simulations of vancomycin and desleucyl-vancomycin. Our simulations provided atomic details of
vancomycin and related compounds binding with cell wall peptide. According to our simulations,
desleucyl-vancomycin doesn’t bind to bacterial cell wall tightly even under restraints based on solid
nuclear magnetic resonance (NMR) experimental results. This agrees with the fact that desleucyl-
vancomycin is a much less antibiotic than vancomycin.
Physical/Computational Chemistry 2 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 121
Control of C-H Activation by Mo-Oxo Complexes: pKa or BDFE?
Azadeh Nazemi, Thomas R. Cundari*
Department of Chemistry, Center of Advanced Scientific Computing and Modeling (CASCaM),
University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Based on previous research in our group, the deprotonation of a methyl ligand is a competing side
reaction in the reductive functionalization (RF) of metal-methyl complexes.1,2 In this research, a DFT study
was carried out to understand what controls the pKa of C-H bonds, and how these factors impact
competing and productive C-H functionalization processes. First, several levels of theory were calibrated
by optimizing 18 carbon acids for which experimental pKa’s are available. BMK/6-31+G(d)3 was thus
selected as the ideal basis set/functional combination for subsequent calculations, which involved C-H
activation of substituted toluenes by a Mo-oxo complex. Previous studies on RF of metal-methyl
complexes suggested Group 6 as a good target for catalytic functionalization of hydrocarbons.1 A
molybdenum-oxo complex (related to the active site of the enzyme, ethylbenzene dehydrogenase4) with a
potentially redox non-innocent supporting ligand was chosen as a catalyst to investigate C-H activation,
specifically benzylic substrates like toluene and meta/para-substituted-toluene. The purpose is to assess
whether pKa or the bond dissociation free energy (BDFE) – or some other factor – is more important
for facile C-H bond activation via deprotonation (C-H bond heterolysis) or H atom abstraction (C-H bond
homolysis), respectively, pathways.
1. Fallah, H.; Cundari, T, R.; Organometallics. 2016, 35, 950 - 958.
2. Fallah, H.; Cundari, T, R.; Comput. Theor. Chem. 2015, 1069, 86 - 95.
3. Ho, J.; Coote, M.; J. Chem. Theory Comput. 2009, 5, 295 - 306.
4. Szaleniec, M. et al. J. Inorg. Biochem. 2014, 139, 9 - 20.
Physical/Computational Chemistry 2 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 122
Porous Silicon Oxycarbide (SiCO) Materials
Susana Aguirre-Medel, Peter Kroll*
Department of Chemistry & Biochemistry, University of Texas at Arlington
E-mail: [email protected]
Category: Graduate
Division: Physical Chemistry
We report synthesis of porous silicon oxycarbide (SiCO) materials, their microstructural characterization
and performance in environmental applications. One of processes consists of reacting siloxane
precursors containing Si-H bonds with cross-linkers bearing vinyl groups using a platinum catalyst. The
reaction in diluted solutions (80-95 vol%) converts the siloxanes into aerogels after supercritical drying
in CO2. The other synthesis method involves hydrolysis and condensation reactions to obtain a cross-
linked gel which is slowly dried at 45 °C to obtain a porous material.
Porous SiCO materials are transformed via thermal treatment in controlled atmospheres into SiCO
ceramics. In addition, we augment the chemical synthesis by various treatments to tailor microstructural
and chemical properties of aerogels. We characterize the porous SiCO materials’ specific surface area,
nanoparticle size, pore size distribution, average pore size and total porosity. We emphasize the
microstructural tailoring by heat treatment atmosphere and additional post-synthesis methods. We
also study the potential applications of these materials, specifically the effects of different
microstructures on their properties.
Physical/Computational Chemistry 2 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 123
The Role of H-bonding in DNA
Siying Lyu, Elfi Kraka,* Dieter Cremer
Computational and Theoretical Chemistry Group (CATCO), Department of Chemistry, Southern
Methodist University
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
The strands of the DNA double helix are hold together by the hydrogen bonds of the base pairs whereas
the strands themselves are influenced by the conformational flexibility of the deoxyribose rings, which
depends on their pseudolibration modes and the rotation of the side groups. The latter are also
influenced by hydrogen bonding, which couples pseudolibration and side group rotations.
In this work, the strength of the H-bonds keeping the various base pairs together is determined and
compared with that in the deoxyribose rings. Based on the calculated local stretching force constants
of the type O…H or N…H there is a clear preference of H-bonding in the base pairs compared to that in the
deoxyribose rings, which for the first time is quantified. H-bonding in the deoxyribose rings is undergoing
a large amplitude oscillation guided by the pseudolibrational motion of the five-membered ring.
Physical/Computational Chemistry 2 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 124
Computational Study of C-H Activation of Methane by Diiminopyridine Nitride Complexes
Zhicheng (Daniel) Sun, Olivia A. Hull, Thomas R. Cundari*
Department of Chemistry, Center of Advanced Scientific Computing and Modeling (CASCaM),
University of North Texas
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
2,6- diiminopyridine (PDI) complexes have been under intense investigation due to their catalytic ability
and versatility in binding many different metals and main group elements. Some known applications of
PDI complexes involve olefin polymerization, nitrogen-hydrogen bond activation, hydrosilylation, and
hydrogenation. However, there are few reported cases of carbon-hydrogen bond activation via PDI or
nitride complexes. The aliphatic C-H bond is thermodynamically strong and kinetically inert, making it
harder to activate, especially in light alkanes such as methane. Being able to functionalize cheap and
abundant light alkanes through catalysis can avoid traditional combustion technologies, which are
harmful to environment. In our studies, calculations were made using DFT methods and the Gaussian
09 software to study (PhPDI)MN [PhPDI = 2,6-(PhN=CMe)2C5H3N] (M = VIII, MnIII, FeIII, CoIII, NiIII, AlIII, PIII), and
their reactions with methane to form (PhPDI)M—N(H)CH3. Three different methane C-H bond activation
pathways were studied, including insertion, hydrogen atom abstraction (HAA), and [2+2] addition. Our
results show that early transition metals PDI nitride complexes favor the [2+2] pathway, while later
transition metals favor the HAA pathway. Activation barriers and free energy change of reactions were
calculated. Electron density analysis is used to examine the redox non-innocence of the PDI ligand in
these reactions.
Physical/Computational Chemistry 2 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 125
Exploring the Nature and Strength of Chalcogen Bonding for the Rational Design of New Materials
Vytor Oliveira, Elfi Kraka*, Dieter Cremer
Computational and Theoretical Chemistry Group (CATCO), Department of Chemistry, Southern
Methodist University
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Non-covalent interactions guide the self-assembly of macromolecules such as proteins, DNA/RNA,
polymers, and are responsible for drug-receptor recognition, ion-transport, etc. Besides the well-known
hydrogen bonds, chalcogens (O, S, Se, Te) are also able to form short, directional, non-covalent
interactions, called chalcogen-bonding. Since this interaction is less explored than hydrogen bonding and
other non-covalent bonds, chalcogen compounds are interesting candidates for the development of
materials with unique properties. We studied 90 chalcogen-bonded complexes, calculated their local
stretching force constant, and analyzed their electron density distributions. We found out that most
chalcogen bonds involve the charge transfer of lone pair of a heteroatom A to the antibonding orbital
σ*(Y-E) involving the chalcogen E and a suitable atom (group) Y. The strength of chalcogen bonding
depends on the polarizability of E, polarizing power of Y, and electron donor ability of A. In a divalent
chalcogen, the second ligand can enhance the strength of the bond by withdrawing charge from the lone
pair of E and decreasing exchange-repulsion between E and A. There are more possibilities to fine-tune
a divalent chalcogen compared to a monovalent halogen or hydrogen. Based on this study, a receipt for
creating new chalcogen-bonded building blocks is given.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 126
Section 6
Physical/Computational Chemistry 3 Sid W. Richardson Physical Sciences Building: SWR 360
Time Presenter Title
01:30 -01:45 Yunwen Tao Southern Methodist University
Why does warm water freeze faster than cold water? - An explanation based on different ways of hydrogen bonding
01:45-02:00 Dineli Ranathunga University of Texas at Dallas
Molecular Dynamics Simulations of Glutathione coated Gold Nanoparticles
02:00-02:15 Hongyu Zhou Southern Methodist University
Direct Pathway Dynamics Sampling
02:15-02:30 Seunga Kim Texas A&M University – Commerce
Co-precipitation synthesis of palladium and cerium solid solution as efficient catalysts for selective hydrogenation of acetylene in ethylene
02:30-02:45 Li Shen Southern Methodist University
Catalytic Mechanism of β-Lactamases:
Chemical Driving Force behind Antibiotic Resistance
02:45-03:00 Alan Humason Southern Methodist University
Deciphering the Nature of the Pancake Bonding Interaction - Are these the Longest Bonds is Chemistry?
Physical/Computational Chemistry 3 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 127
Why does warm water freeze faster than cold water? - An explanation
based on different ways of hydrogen bonding
Yunwen Tao,† Wenli Zou,† Junteng Jia,‡ Wei Li,‡ Dieter Cremer*,†
†Department of Chemistry, Southern Methodist University
‡Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic
Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, China
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Water has many unusual physical and chemical properties, which are related to the network of hydrogen
bonds in the liquid. One of the most peculiar properties leads to the observation that warm water freezes
faster than cold water (Mpemba effect). Knowledge and use of the Mpemba effect goes back to Aristotle
(350 AC), Francis Beacon (1561-1626), or Rene Descartes (1596-1650) who all described the use of
this effect. The Mpemba effect is as interesting as it has been discussed controversially in the literature.
We investigated changes in the hydrogen bond network of liquid water using molecular dynamics
simulations. We could identify 36 different hydrogen bonding situations of which 16 are relevant for the
discussion. We determine the temperature dependence of H-bonding showing that at higher
temperature weaker H-bonds are broken whereas strong H-bonds dominantly remain. Our results
provide a molecular explanation of Newton’s law of cooling and the Mpemba effect.
Physical/Computational Chemistry 3 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 128
Molecular Dynamics Simulations of Glutathione coated Gold
Nanoparticles
Dineli Ranathunga, Steven O. Nielsen*
Department of Chemistry & Biochemistry, University of Texas at Dallas
E-mail: [email protected]
Category: Graduate
Division: Physical Chemistry
Ligand coated gold nanoparticles have shown promise in many bio-medical applications such as cancer
detection, clinical chemistry, biosensors and targeted drug delivery. Use of glutathione as the ligand has
been shown to give a renal clearable fluorescent probe. The organization of the ligands on the gold
surface has been shown to affect the emission wavelength. The organization can be affected by the pH
and the ligand density. Here we show a general method to prepare glutathione coated gold nanoparticles
for study using molecular dynamics computer simulations. We determined that the ligand density
depends on the curvature of the gold surface and is smaller than that of straight chain ligands such as
alkane thiols. This general method will be applied to study the physical properties of different biosensors
built on this platform.
Physical/Computational Chemistry 3 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 129
Direct Pathway Dynamics Sampling
Hongyu Zhou, Peng Tao*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Molecular Dynamics is a sophisticated method to deal with the protein dynamics problem. However, the
deficient sampling space in protein system becomes a limitation of this method. Therefore, enhancing
sampling has raised enormous interests in this area. In the current work, a new method named Direct
Pathway Dynamic Sampling has been developed. Here we applied a well-known reaction pathway
searching method, the Chain-of-States method, to perform molecular dynamics simulation. The result
has showed a strongly sampling efficiency increasing compared with normal simulations. Several testing
cases in different scales have been conducted. Starting with a simple example, alanine dipeptide, the
sampling efficiency has been thoroughly investigated. A complete contour plot has been generated to
show the sampling space. The huge sampling efficiency increasing of our method proved the
effectiveness of our method. Besides that, the beta-hairpin peptide folding process and beta-lactam
dissociation reaction process have also been thoroughly investigated. All those cases show a great
increasing sampling efficiency of our DPDS method compared with normal MD simulation. In conclusion,
the new developed method, Direct Pathway Dynamics Sampling has been successfully enhanced
sampling compared with normal molecular dynamics simulation.
Physical/Computational Chemistry 3 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 130
Co-precipitation synthesis of palladium and cerium solid solution as
efficient catalysts for selective hydrogenation of acetylene in ethylene
Seunga Kim, Ben W.L. Jang*
Department of Chemistry, Texas A&M University – Commerce
E-mail: [email protected]
Category: Graduate
Division: Physical Chemistry
Palladium based materials are well-known commercial catalysts for selective hydrogenation of acetylene
in ethylene for the multi-billion polyethylene industry. Recently, ceria has been demonstrated to show high
selectivity and considerable activity for selective hydrogenation at high temperatures. The objective of
this investigation is to develop ceria based catalysts with high activity and high selective for the selective
hydrogenation of acetylene in ethylene at lower temperatures. The approach is to combine Pd with ceria
into one catalyst system using the co-precipitation technique followed by post treatment procedures.
Such Pd-ceria catalysts with 0.15% and 0.2% of Pd have been synthesized and studied at various
temperatures, including 50℃, 75℃, 100℃, 125℃, 150℃, 175℃, and 200℃ after 1 hour of hydrogen
reduction at 200℃. The results show that the activity of 0.15%Pd-ceria is good with ~90% conversion
at 100C. However, its selectivity is below 0% due to the hydrogenation of ethylene in the feed. Calcination
at 600C decreases its activity but increases the selectivity. Further investigation on the effects of the
calcination time and temperature as well as hydrogenation reduction temperature on the behavior of
the catalyst will be studied and compared with the 0.2%Pd-ceria catalyst samples.
Physical/Computational Chemistry 3 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 131
Catalytic Mechanism of β-Lactamases: Chemical Driving Force behind
Antibiotic Resistance
Li Shen, Peng Tao*
Department of Chemistry, Southern Methodist University
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
β-Lactamases are enzymes that hydrolyze β-lactam antibiotics. They are the main cause of antimicrobial
resistance, and continuously evolve adaptive mechanisms in a biological arms race with the development
of antibiotics. Elucidating and predicting β-lactamase evolution are crucial for the future development of
antibiotics with low or even no resistance. β-Lactamases cause antibiotics resistance by breaking the β-
lactam ring of antibiotics, rendering them ineffective. Therefore, we carried out hybrid quantum
mechanical and molecular mechanical (QM/MM) calculations within chain-of-states framework to
obtain minimum energy pathways (MEP) representing catalytic mechanisms of key β-lactamases. These
pathways from different β-lactamases are superimposed and compared to shed lights on evolution of β-
lactamase catalytic mechanisms. TEM-1(class A), DD-peptidase and penicillin binding protein A (PBP-A)
are investigated. Key structures along the reaction pathways of TEM-1, DD-peptidase and PBP-A are
superimposed. The results show that these proteins have similar structures along the pathways.
Reaction mechanism of penicillin-G hydrolysis is conserved among TEM-1 (Class A β-lactamase), DD-
peptidase and PBP-A, confirming our hypothesis that catalytic mechanisms are conserved among these
related proteins.
Physical/Computational Chemistry 3 SWR 360
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 132
Deciphering the Nature of the Pancake Bonding Interaction – Are
these the Longest Bonds is Chemistry?
Alan Humason, Dieter Cremer*
Computational and Theoretical Chemistry Group (CATCO), Department of Chemistry, Southern
Methodist University
E-mail: [email protected]
Category: Graduate
Division: Computational Chemistry
Free radical molecules are generally short-lived because of their tendency to selfdimerize into more
stable covalently bonded species. Mulliken proposed that novel chemistry could be observed by creating
a sterically hindered free radical molecule, which could not dimerize, due to steric repulsion. He named
this proposed, but unobserved, interaction ‘pancake bonding.’
Once synthesized, studies of magnetic properties and X-ray structures of these pancake bonded
compounds found that the molecules exist as stacked dimers, at distances longer than normal covalent
bonding distances, but shorter than the sum of their van der Waals radii. This led to speculations about
the nature of the interaction.
In this work, we employ quantum chemistry (Coupled Cluster and DFT methods) to study the bond/dimer
dissociation energies of five pancake bonded species. We use the analysis of vibrational modes to
determine the local stretching force constants between the dimers, which give a reliable measure of the
strength of the interaction between them. We use the critical points of the electron density distribution
to characterize the interactions between the monomers. We demonstrate that pancake bonding is not
a covalent bonding interaction, and that the so-called ‘pancake bonds’ are a result of dispersion
interactions between two radicals.
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 133
Presenters Index
Presenting Author Page # Presenting Author Page #
Adam Montoya 109 Gayan A. Appuhamillage 78
Aditi Nagar 94 Habtom B. Gobeze 86
Ahmad Najafian 113 Hannah Johnston 55
Alan Humason 132 Hector Villegas 15
Alexander T. Brown 46 Hiep Nguyen 85
Anne D’Achille 63 Hongyu Zhou 129
Anthony B. Samuel 14 Iain W. H. Oswald 26
Apparao Bokka 87 Jacob W. McCabe 67
Apsara K. Herath 83 Jason B. Miller 89
Audrey Reeves 13 Jason Lin 30
Avichal Vaish 41 Jayendra Chunduru 101
Azadeh Nazemi 121 Jian Cao 91
Brandon J. Foley 22 Jonathan Buford 57
Brian L Kamras 49 Joshua Burge 20
Brooke M. Otten 40 Joshua F. Ivy 51
Caleb M. Bunton 105 Juan P. Vizuet 31
Charles Ochoa 104 Katherine A. Benavides 43
Christiana Agbo 18 Kelly Schostag 12
Christopher O. Obondi 108 Kenneth J. MacKenzie 59
Christopher Parish 118 Khaled Shennara 61
Christopher Williams 58 Kortney M. Melancon 47
Daniel Korir 54 Lauren M. Harris 34
Darrell D. Mayberry 27 Lawton A. Seal II 100
Diego F. Zometa 9 Li Shen 131
Dineli Ranathunga 128 Lindsay Davis 90
Do Nguyen 44 Luke Ryan 80
Enrique Barragan 73 Mackenzie Young 11
Erik Antonio V. Montelongo 114 Maddie M. Barnett 7
Erin N. Benton 38 Maha Aljowni 97
Feng Wang 120 Maribel Barrera 5
Dallas-Fort Worth Section of the American Chemical Society
50th Annual Meeting-in-Miniature Organized By: Department of Chemistry & Biochemistry, TCU 134
Presenting Author Page # Presenting Author Page #
Marlius Castillo 107 Sinjinee Sardar 64
Melissa Orr 4 Siying Lyu 123
Miguel E. Quimbar 21 Stephanie I. Jones 116
Mikaela Wilk 29 Stephen M. Budy 77
Misty S. Martin 19 Sulihat Mudasiru 95
Mohammed Irfan Zakir Omer 62 Susana Aguirre-Medel 122
Nimmy Mammoottil 75 Swetha Chinthala 70
Noonikara Poyil 92 Taniya M.S.K. Pathiranage 68
Olatunji Ojo 93 Tharun T. Ponduru 48
P. Sotelo 50 Thirupataiah Avullala 76
P.B Jayathilaka 52 Thomas Howlett 16
Parham Asgari 69 Udaya Sree Dakarapu 99
Patricia Nance 6 Vishal Rajat Sharma 110
Pawan Thapa 84 Vytor Oliveira 125
Peter Niedbalski 112 Waleed Yaseen 28
Philip M. Palacios 36 Wijayantha A. Perera 37
Qing Wang 115 Yakun Cao 33
Rajesh Kumar 65 Yi Hu 71
Ravi P. Singh 82 Yixin Ren 25
Riffat Parveen 117 Yunwen Tao 127
Robert Green 102 Zhicheng (Daniel) Sun 124
Ruaa Almotawa 56
Samantha M. Brewer 35
Sampath B. Alahakoon 98
Samuel Weber 23
Sanjana Ravi 8
Seunga Kim 130
Seyed Majid Farvid 42
Shital Kale 106
Shivaraj Yellappa 72
Shreya Patel 3
Shuai Shao 79