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1
12th Australasian
Organometallics
Meeting
Abstract Book
School of Chemistry,
The University of Melbourne
9th - 12th July 2019
2
Table of Contents
Welcome…………………………………………….3
Map of Campus…………………………………….4
Programme………………………………………….5
Plenary Lectures………………………………….12
Keynote Lectures…………………………………16
Special Topic Presentations……………………20
Oral Presentations………………………………..22
Poster Presentations…………………………….56
List of Attendees………………………………….98
3
Welcome We welcome you to the 12th Australasian Organometallics Meeting – OZOM12 – back
again in Victoria. In maintaining the previous tradition of these successful
meetings, OZOM12 has its focus on presentations from students and early career
researchers, supported by 4 plenary lectures, 4 keynote lectures and 2 special topic
presentations. The conference covers various aspects of fundamental and applied
organometallic chemistry, including:
• Organometallic chemistry of main, transition, and lanthanoid elements
• Structure and reactivity
• Catalysis
• Asymmetric synthesis
• Theoretical chemistry
• Bio-organometallic chemistry
• Application of organometallic complexes in life science
• Application of organometallic complexes in materials science
• Synthetic chemistry
We thank the School of Chemistry, The University of Melbourne for hosting the
meeting, with lectures being held in the historic Masson Theatre in the School of
Chemistry. We acknowledge the generous support of our sponsors, listed on page 11.
We hope you enjoy yourselves.
The OZOM12 organizing committee:
Richard O’Hair, Chair
Vicki Blair, Treasurer
Carol Hua
Melissa Werrett
Paul Donnelly
4
5
12th Australasian Organometallics Meeting
Programme (OZOM12)
Tuesday 9th July 2019
Registration 15:00 – 17:00
17:00 Opening Address
17:10 Plenary 1 | Penelope Brothers | The chemistry of boron with pyrrole ligands:
tales from the world of porphyrins, corroles, phthalocyanines and BODIPY
Chair: Victoria Blair
18:00 BBQ and Drinks
Wednesday 10th July 2019
9:00 Plenary 2 | Frank Edelmann | My 40-year organometallic journey through the
Periodic Table with frequent stops at the rare-earth elements
Chair: Carol Hua
Session Chair: Ben Frogley
9:50 Alasdair McKay | A Mechanistically Guided Approach to C-H Bond Amidation
10:10 Daven Foster | In-depth study of a Highly Efficient Enantioselective
Intramolecular Hydroamination Reaction
10:30 Morning Tea
11:00 Keynote 1 | Melissa Werrett | Bismuth Nanocellulose Composites and their
Efficacy Towards Multi-Drug Resistant Bacteria
Session Chair: Koushik Venkatesan
11:30 Isabelle Dixon | Theoretical insights into ligand photorelease mechanisms: new
types of 3MC states
11:50 Harrison Barnett | Detection and Reactivity of a Bridging C1 Ligand
12:10 Angus Gillespie | Synthesis and Properties of 2,7-alkynyldihydropyrene
Photochromic Switches
12:30 Lunch Break
13:30 Keynote 2 | Rebecca Fuller | A tale of two cities: Electrostatic potentials are a
chemists best friend and new beginnings with trigonal lanthanoid magnets
Session Chair: Stacey Rudd
14:00 Jamie Greer | Accessing unsupported magnesium 2-aza allyl complexes
14:20 Lynn Lisboa | Switchable Heterometallic Supramolecular Cages
14:40 Albert Paparo | Beryllium
6
15:00 Frédéric Paul | Porphyrins and Electron-Rich Alkynyl Complexes: A Step toward
Remarkable Redox-active Molecular Arrays for Electronics or Photonics
15:20 Michael Stevens | Extending Alkali Metal Mediated Magnesiation from nitrogen
to phosphorus
15:40 Afternoon Tea
Session Chair: Marcus Korb
16:10 Samantha Orr | Sodium-magnesiate facilitated cyclisation of imines via C-F bond
activation
16:30 Alphonsine Ngo Ndimba | Tris(styryl)isocyanurates: Towards New Dyes with
Large Two-Photon Absorption Cross-Sections
16:50 Jamie Hicks | Nucleophilic aluminium: Synthesis, structural and reaction
chemistry of the aluminyl anion
17:10 Angus Shephard | New aluminium lanthanoid biphenolate complexes through
redox transmetallation protolysis
17:30 Jeremy Stone | Synthesis of ruthenium diimine complexes for catalysis
Lightning Talk Chair: Albert Paparo
17:50 Lightning Talk 1 | James Findlay
17:55 Lightning Talk 2 | Curtis Ho
18:00 Lightning Talk 3 | Mahbod Morshedi
18:05 Lightning Talk 4 | Rachel Steen
18:10 Lightning Talk 5 | Kuppusamy Yuvaraj
18:15 Lightning Talk 6 | Linda Zhang
18:20 Poster Session
Thursday 11th July 2019
9:00 Plenary 3 | Monica Perez-Temprano | Synergistic Cooperation between
Mechanistic Investigations and Catalysis: Towards Rational Design
Chair: Melissa Werrett
Session Chair: William Erb
9:50 Kirralee Burke | Exploring properties of novel Ga(III) and Bi(III) flavonolate
complexes
10:10 Howard Ma | Caught at Last! Isolation, Structural Characterization and Gas-
phase Studies of the [Ag10(H)8L6]2+ Nanocluster Dication
10:30 Morning Tea
7
11:00 Keynote 3 | Nick Cox | High-Field Pulse EPR: A New Biophysical Toolbox for
the Study of Metalloenzymes
Session Chair: Alasdair McKay
11:30 Margaret Aulsebrook | From Reactor to Radiotracer at ANSTO - Increasing the
Availability of Non-routine Radionuclides
11:50 Max Roemer | Robust and Recyclable Hybrid Rhodium- and Iridium-Catalysts
with Long Alkyl Tethers
12:10 Sarmishta Munuganti | An Exploration into the synthesis and microbial activity
of some heterocyclic bismuth-based complexes
12:30 Lunch Break
Special workshop for ECRs | Professors Lou Rendina, Mark Humphrey, Paul
Low | The ARC assessment process
13:30 Keynote 4 | Annie Colebatch | Main Group Pyridyl Ligands: From the Molecular
to the Supramolecular
Session Chair: Fred Paul
14:00 Matthew Gyton | A convenient method for the generation of [Rh(PNP)]+ and
[Rh(PONOP)]+ fragments: reversible formation of vinylidene derivatives
14:20 Benjamin Frogley | Heteroatom-Bridged Transition-Metal Carbynes
14:40 Angelo Frei | Multifunctional Cyclopentadiene Ligands for Theranostic
Approaches with Re and 99mTc
15:00 Sinead Keaveney | Palladium-Catalyzed Decarbonylative Trifluoromethylation of
Acid Fluorides
15:20 Mohammad Al Bayer | Synthesis of difluorogold(III) complexes supported by
N-ligands
15:40 Afternoon Tea
Session Chair: Isabelle Dixon
16:10 Nimrod Eren | Insights into the s-Block Metalations of Allylic Phosphines and
Phosphine Oxides
16:30 Rebekah Duffin | Anti-Leishmanial Activity of Organometallic Antimony (V) And
Gallium (III) Quinolinolato Complexes
16:50 Robert Malmberg | Tunable Photoluminescent Properties of a New Class of
Thermally Robust Monocyclometalated Gold(III) Complexes
17:10 Marcus Korb | Reactions of Planar-Chiral 1-P(S)Ph2-2-CH2OH Ferrocenes
17:30 Special Topic 1 | Ian Rae | Nineteenth Century Organometallics in Melbourne
Chair: Richard O’Hair
19:00 Conference Dinner | La Spaghetteria Ristorante | 132 Lygon St, Carlton
8
Friday 12th July 2019
9:00 Plenary 4 | Heinrich Lang | From: Small Tailor-made Molecules To: New
Materials
Chair: Paul Donnelly
Session Chair: Curtis Ho
9:50 Masnun Naher | Metal Complexes for Molecular Electronics: Explorations of
Thioether Anchor Groups
10:10 Sigrídur Suman | Ligand Exchange Reaction and Catalysis of the Conversion
of Cyanide and Thiosulfate to Thiocyanate and Sulfite by a Molybdenum
Complex
10:30 Morning Tea
Session Chair: Jamie Hicks
11:00 Nicholas Tan | Rhodium (I)-Vinyl Complexes as Effective Initiators in the
Stereospecific Polymerization of Phenylacetylene
11:20 William Erb | An unprecedented diversity of 1,3-disubstituted ferrocenes through
the halogen ‘dance’ reaction
11:40 Zhifang Guo | Direct reaction—a simple route to synthesis
organoioamidodidolanthanoid(II/III) complexes
17:30 Special Topic 2 | Mark Rizzacasa | Married at First Sight: Total Synthesis and
Metal Complexes
Chair: Richard O’Hair
12:30 BBQ and Drinks
Poster Presentations
P1 Weam Altalhi | A Mechanistic Study of Ruthenium (II) Catalysed C-H Amidation and
Thioamidition
P2 Stephen Best | Charting the Reaction Coordinate in ‘Beryllocene’
P3 Lian Burt | Alkynyltellurolate Ligands and a Solvatochromic Rhenium(I) Complex
P4 Chiara Caporale | Single-Molecule Magnets: Lanthanide - β Diketonates “Triangles”
P5 Glen Deacon | Use of Ag(C6F5) or Bi(C6F5)3 instead of HgAr2 reagents in redox
transmetallation/protolysis reactions of free lanthanoid metals
P6 Deepamali Dissanayake | Lewis acids: Versatile catalysts for fundamental
transformations and polymerisations
P7 Jun Du | Optical Nonlinearities of Y-shaped and H-shaped Arylalkynylruthenium
Complexes
9
P8 James Findlay | A [3]Rotaxane With Coupled Rotary and Linear Shuttling Motion
P9 Palak Garg | Bimetallic Group 14 Complexes Stabilised by Bis(N,N’-diarylamidinate)
Ligand
P10 Chuanzhu Gao | Antitumor dinuclear platinum (II) complexes with DNA imbedding
groups
P11 Michael Hall | Synthesis and Reactivity of Carbon-Rich and Cumulenylidene Ligands
in Iron and Ruthenium Complexes
P12 Daniel Harrison | Simple Metalation of Terminal Acetylenes: Synthesis of High Purity
Metal Acetylide Half- Sandwich Complexes
P13 Megan Herdman | Bismuth(III) phosphinate 1D-coordination polymers as
antibacterial additives
P14 Curtis Ho | Applications of Gold Cocatalysis & New Phosphine Ligands for Palladium-
Catalysed Cross-Couplings
P15 Ryan Huo | Confirmation of Redox Transmetallation/Protolysis Reaction Between
HgC6F5, lanthanoid metals and protic agents
P16 Dafydd Jones | Synthesis of New, Super Bulky β-Diketiminate Ligands and their
Application in Low-Oxidation State Metal Chemistry
P17 Marcus Korb | Diferrocenyl Co- and Fe-Carbonyl Clusters
P18 George Laffan | Synthesis and Spectroelectrochemical Studies of Ruthenium Alkynyl
Complexes
P19 Richard Manzano | The odd nature of tungsten C3 and C5 complexes
P20 Aidan McKay | Towards the Assembly Triple Hydrogen Bonded Transition Metal
Complexes
P21 Mahbod Morshedi | A Dipolar Molecular Switch for Nonlinear Optics
P22 Shazia Nawaz | Synthesis and characterization of bismuth (III) phosphonates as
antimicrobial polymeric materials
P23 Asif Noor | A one-pot route to thioamides and Amidines discovered by fundamental
gas-phase studies
P24 Richard O’Hair | A New Approach to Design MOF Based Catalysts
P25 Chee Onn | Selenium functionalised metal-carbon chains –
Alkynylselenolatoalkylidynes (LnMC–Se–CCR)
P26 Parvin Safari | Electron transfer processes and mixed-valence chemistry: studies with
metal complexes featuring carbon-rich ligands
P27 Lachlan Sharp-Bucknall | Reactivity of Newly Discovered Trans-Difluorogold(III)
Complexes
P28 Cory Smith | Experimental and Theoretical Properties of Low-Oxidation State
Aluminium Amidinate Complexes
10
P29 Nigel Lucas | Superphenylphosphines: Nanographene-based Ligands that Direct
Coordination and Bulk Assembly
P30 Rachel Steen | Selective Activation of Alkynes through Cumulene Intermediates
P31 Lian Stephens | Synthesis of Novel Bismuth Tetrazole Thiolate Complexes as
Potential Antimicrobials
P32 Sigridur Suman | Biological Studies of a Molybdenum based Cyanide Poisoning
Antidote
P33 Yu Qing Tan | A new rotational isomer of bis(pentafluorophenyl)mercury [Hg(C6F5)2]
P34 Quinn van Hilst | Synthesis, Characterization and Biological Activity of Select [Pt(2-
pyridyl-1,2,3-triazole)2]2+ “Click” Complexes
P35 Daniel Van Zeil | Catalytic activity of N-heterocyclic carbene Ag(I) amides
P36 Koushik Venkatesan | Deep Blue Organic Light Emitting Diodes Based on N-
Heterocyclic Carbene Platinum(II) Complexes
P37 Huan Wang | Synthesis, Linear Optical, and Second-/Third-Order NLO Properties of
Porphyrin-Bridged Push-Pull Ruthenium Complexes
P38 Zilin Wang | Desulfination versus decarboxylation as a means of generating three-
and five- coordinate organopalladium complexes [(phen)nPd(C6H5)]+ (n = 1 and 2) to
study their fundamental bimolecular reactivity
P39 Steven Welsh | Early transition metal poly(methimazolyl)borate complexes
P40 Yang Yang | A novel transition-metal assisted approach to amide synthesis directed
by mechanistic studies
P41 Kuppusamy Yuvaraj | Reductive Trimerization of CO to the Deltate Dianion using
Activated Magnesium(I) Compounds
P42 Ling Zhang | Towards High-Generation Ruthenium Alkynyl Dendrimers for Nonlinear
Optics
11
The Organising Committee gratefully acknowledges the support of our
sponsors:
Plenary Lectures
12 12th Australasian Organometallics Meeting
The chemistry of boron with pyrrole ligands: tales from the
world of porphyrins, corroles, phthalocyanines and
BODIPY
Penelope J. Brothers
Research School of Chemistry, Australian National University
Over recent years we have investigated the chemistry of boron with pyrrole-containing
ligands, of which the best known are porphyrins. Boron porphyrins are unique in
containing two boron atoms per porphyrin ligand. Highlights of this chemistry have
been the development of a diboryl porphyrin and a diboranyl porphyrin containing a
B-B bond which forms through spontaneous reductive coupling of the diboryl. More
recent work extends the coordination of boron to further ligands in the tetrapyrrole
family, notably corrole, phthalocyanine, porphyrazine and calixphyrin. Although these
ligands are closely related, we observe some significant differences in the boron
chemistry, including stereochemistry and chemical reactivity. As an example, we have
isolated boron hydride corrole complexes, including an unusual example of a complex
containing a B-H-B group coordinated to the cavity in the corrole. Finally, the well-
known BODIPY fluorophore is a boron dipyrrole complex, and using our expertise on
the chemistry of boron we have been prepared BODIPY-carbohydrate conjugates
which may have application ion sugar sensing and carbohydrate structure and
function.
B2OF2(porphyrin) B2OF2(corrole)
B2HPh2(corrole)
Plenary Lectures
13 12th Australasian Organometallics Meeting
My 40-year organometallic journey through the Periodic
Table with frequent stops at the rare-earth elements
Frank T. Edelmann
Chemisches Institut der Otto-von-Guericke-Universität Magdeburg, Germany
This lecture is intended to provide an overview of the various aspects of our
organometallic chemistry studied at different universities (Hamburg, Edmonton,
Honolulu, Calgary, Göttingen and Magdeburg) during the past four decades. Early
highlights include e.g. the synthesis of CpCoS2N2, the first diaryl lead compound,
Pb[C6H2(CF3)3-2,4,6]2, and the dimerization of a phosphaalkyne by reaction with
decamethylsamarocene. Publications from Göttingen during the late 80's and early
90's on f-element amidinates made very clear the broad scope for new and possibly
useful chemistry offered by amidinate and related diazaallylic ligands. More recent
exploration of metallasilsesquioxanes and various sandwich complexes (including
triple- and tetra-decker sandwich complexes) of lanthanides and actinides will also be
described.
Word cloud illustrating our main research interests
Plenary Lectures
14 12th Australasian Organometallics Meeting
Synergistic Cooperation between Mechanistic
Investigations and Catalysis: Towards Rational Design
Mónica H. Pérez-Temprano*
Institute of Chemical Research of Catalonia (ICIQ)
The sustainable synthesis of relevant organic scaffolds for their use in the
pharmaceutical, agrochemical and material sectors constitutes one of the most urgent
challenges that the chemical community needs to overcome. Our ideal approach for
tackle this problem is the rational design and development of catalytic processes
based on fundamental mechanistic understanding. Surprisingly, this strategy remains
a largely unresolved challenge for academic and industrial chemists.
This work will describe our recent efforts not only to provide critical mechanistic
information on well-known reactivity, but also to understand, discover, design and
develop more efficient transition metal-catalyzed reactions by trapping and/or
synthesizing key reaction intermediates and using them as “knowledge building
blocks” for rational design (Figure 1).[1]
Figure 1. Our approach: trapping reaction intermediates for rational design.
References
[1] (a) J. Sanjosé-Orduna, D. Gallego, A. Garcia-Roca, E. Martin, J. Benet-Buchholz, M. H. Pérez-
Temprano, Angew. Chem. Int. Ed. 2017, 56, 12137. (b) J. Sanjosé-Orduna, J. M. Sarria Toro, M. H.
Pérez-Temprano, Angew. Chem. Int. Ed. 2018, 57, 11369.
[TM]
[TM]
[TM] ✓ improving the efficiency of
well-established transformation
✓ exploring innovativereactivity patterns
Trapping Reaction Intermediates as
“Knowledge Building Blocks”
Plenary Lectures
15 12th Australasian Organometallics Meeting
From: Small Tailor-made Molecules
To: New Materials
Heinrich Lang
Technische Universität Chemnitz, Faculty of Natural Sciences, Inorganic Chemistry
Within this presentation a brief overview of our group’s topics in the field of Material
Sciences will be given.
One focus of the talk will be directed to the use of organometallic and metal-organic
compounds based on different transition metals (for example, Cu, Ru and Co) as
precursor molecules in gas-phase (Chemical Vapour Deposition, Atomic Layer
Deposition) and spray-coating deposition technologies for the generation of thin,
dense and conformal metal films and patterns.
Also the use of combustion-CVD and especially 2D-inkjet printing of metal-organic
inks to produce conductive and semi-conductive layers on flexible substrates will be
discussed.
A straightforward synthetic methodology for the generation and stabilization of
conductive and magnetic metal as well as metal oxide nanoparticles by using single-
source complexes, including LnM(O2CCH2(OCH2CH2)2OMe)m (LnM = Ag, Cu(PR3)2,
Au(PR3), Ru(PR3)2(CO)2, Pd(PR3)2, Pt(PR3)2, Rh, Mn, Co, Ni, Fe, …; m = 1, 2, 3) as
precursors will be envisaged.
Finally, the possibility to apply metal nanoparticles for joining materials at low
temperature using the soldering process will be reported, as well as laser ablation for
the generation of metallic structures from metal-organic complexes.
Keynote Lectures
16 12th Australasian Organometallics Meeting
Bismuth Nanocellulose Composites and their Efficacy
Towards Multi-Drug Resistant Bacteria
Melissa V. Werrett,1 Megan E. Herdman,1 Liam J. Stephens,1 Rajini Brammananth2
Warren Batchelor,3 Maisha Maliha3 and Phil C. Andrews1*
School of Chemistry,1 Department of Microbiology2 and BioPRIA: Department of Chemical Engineering,3 Monash University.
Antimicrobial resistance is causing an alarming number of deaths in hospitals and
healthcare facilities. Medical devices (eg: bandages, implants) are high risk areas
regarding infection. Silver and its compounds are often used as additives in
antibacterial materials since they display broad spectrum activity, at relatively low
loadings.1 However, the predominance of silver in a range of broad-spectrum
antimicrobial products has generated significant concerns surrounding toxicity,
environmental accumulation and acquired bacterial resistance.2 Consequently, there
is a crucial need to find new, safe alternatives to silver-based antimicrobial additives.
A series of poorly soluble phenyl bis-phosphinato bismuth(III) complexes
[BiPh(OP(=O)R1R2)2] have been synthesised and characterised, and shown to have
effective antibacterial activity against Escherichia coli (E. coli), Staphylococcus aureus
(S. aureus), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-
resistant Enterococcus (VRE).3
The bismuth complexes were incorporated into microfibrillated (nano-) cellulose
generating a bismuth-cellulose composite, as paper sheets or hydrogels. Antibacterial
evaluation indicates that the Bi-cellulose materials have analogous or greater activity
against Gram positive bacteria when compared with commercial silver-based
additives (Figure 1).
Figure 1: (Left) Backscattered electron
image of the Bi-nanoceullose
composite. (Right) Zone of inhibition
assay against VRE, using the Bi-
nanoceullose composite. Bismuth
complex loaded at 0, 0.1, 0.5, 1 and 5
wt%. Ag: silver sulfadiazine at 0.5 wt%.
References
[1] K. Mijnendonckx, N. Leys, J. Mahillon, S. Silver and R. Van Houdt, BioMetals, 2013, 26, 609–621.
[2] J.Y. Maillard and P. Hartemann, Crit. Rev. Microbiol., 2013, 39, 373–383.
[3] M. V. Werrett, M. E. Herdman, R. Brammananth, U. Garusinghe, W. Batchelor, P. K. Crellin, R. L. Coppel and P. C. Andrews, Chem. Eur. J., 2018, 24, 12938–12949.
Keynote Lectures
17 12th Australasian Organometallics Meeting
A tale of two cities: Electrostatic potentials are a chemists
best friend and new beginnings with trigonal lanthanoid
magnets
Rebecca O. Fuller
School of Molecular and Life Science, Curtin University, Bentley, WA
Organometallic chemistry and magnetism have always seem to be a part of the
chemist I am. Primarily during my PhD, organometallic molecules were used as
precursors for the synthesis of magnetic particles. It was only later during my
postdoctoral studies I was introduced to the wonderful world of group 8
cyclopentadienyl dicarbonyl metal halides [CpxM(CO)2X].[1] I learnt how electrostatic
potentials and Hirshfeld surfaces can be used to generate a wealth of knowledge
about these fascinating molecules. I will share with you a little of this story and how
distant interactions rather than close van der Waals contacts played a significant role
in the crystallisation of cyclopentadienyl ruthenium bromide with hexabromoethane.[2]
After recently commencing a DECRA at Curtin University my research focus has
shifted to the development of new magnetic molecules based on pyridyl-
betadiketonates and verdazyl ligands. To date trinuclear lanthanoid systems for the
investigation of toroidal spin arrangements have been prepared. We have also made
significant steps towards the synthesis of a radical ligand to be use to form complexes
with an organolanthanide species.
(left) Hirshfeld surface use to depict close contacts. (right) Trinuclear TbIII complex.
References
[1] R. O. Fuller, C. S. Griffith, G. A. Koutsantonis et al. CrystEngComm, 2012, 14, 812.
[2] R. O. Fuller, C. S. Griffith, G. A. Koutsantonis et al. CrystEngComm, 2012, 14, 804.
Keynote Lectures
18 12th Australasian Organometallics Meeting
High-Field Pulse EPR: A New Biophysical Toolbox for the Study of
Metalloenzymes
Nick Cox
Research School of Chemistry, Australian National University, Acton ACT, Australia
High-field Pulse Electron Paramagnetic Resonance (EPR) has recently emerged as a
powerful technique in the study of biological systems [1]. It represents a sensitive, non-
invasive, site-selective spectroscopy for the analysis of both molecular and
macroscopic properties. With the support of the ARC and the Max Planck Institute for
Chemical Energy Conversion in Mülheim, we are establishing Australia’s first high-
field (3 T, W-band) pulse EPR facility unique to the Asia-Pacific region and designed
to serve EPR spectroscopists across Australia. EPR at higher magnetic fields
enhances sensitivity [1], extends the range of systems amenable for study, and allows
implementation of new cutting-edge multidimensional pulse EPR methods [2].
In this talk I will describe results on nature’s water splitting catalyst, a pentaoxygen
tetramaganese calcium (Mn4O5Ca) cofactor that is found in a unique pigment–protein
complex known as Photosystem II. Structural evolution of the cofactor through its
catalytic (S-state) cycle can be correlated with its magnetic spin state. In “inactive” S-
states the cofactor adopts a low ground spin state whereas in the “active” S-states it
instead adopts a high spin ground state [3]. Intermediates which facilitate cofactor
activation can be isolated and characterized. It is this structural flexibility that allows
redox tuning of the cofactor and provides a means via which the substrate water
access to the cofactor is regulated [4].
References
[1] Cox N, Nalepa A, Pandelia ME, Lubitz W, Savitsky A. Methods in enzymology 563, 211-249 (2015)
[2] Cox N, Retegan M, Neese F, Pantazis DA, Boussac A, Lubitz W. Science 345, 804-808 (2014)
[3] Krewald V, Retegan M, Neese F, Lubitz W, Pantazis DA, Cox N. (2016) Inorg. Chem. 55, 488-501
[4] Perez-Navarro M, Neese F, Lubitz W, Pantazis DA, Cox N. (2016). Curr. Opin. Chem. Biol. 31, 113-119.
Keynote Lectures
19 12th Australasian Organometallics Meeting
Main Group Pyridyl Ligands: From the Molecular to the
Supramolecular
Annie L. Colebatch,*,a,b Eric S. Yang,a Alex J. Plajer,a Álvaro García-Romero,c
Andrew D. Bond,a Raúl García-Rodríguez,c and Dominic S. Wrighta
a Department of Chemistry, University of Cambridge, United Kingdom
b Research School of Chemistry, Australian National University, Australia
c Facultad de Ciencias, Universidad de Valladolid, Spain
Pyridyl groups are one of the most widely encountered donor moieties in inorganic
chemistry thanks to their versatility, robustness and tunable nature, finding application
in catalysis, photochemistry, supramolecular and bioinorganic chemistry. Despite their
widespread use, amongst the thousands of pyridyl-derived ligands that are known,
examples featuring main group elements are severely under-represented. We have
incorporated main group elements in tris(pyridyl) ligands, and found that this provides
a new handle by which to modulate ligand properties.[1-3] This offers opportunities to
synthesise stable supporting ligands[2] or incorporate reactive main group sites to take
advantage of their Lewis acidic[1] or Lewis basic[3] nature. Recent work has extended
these molecular ligand design approaches to the preparation of supramolecular
architectures, providing a route to mixed-metal systems.
Figure 1. Examples of molecular and supramolecular structures featuring main group pyridyl ligands.
References
[1] A. J. Plajer, A. L. Colebatch, F. J. Rizzuto, P. Pröhm, A. D. Bond, R. García-Rodríguez, D. S. Wright
Angew. Chem. Int. Ed. 2018, 57, 6648 – 6652.
[2] A. J. Plajer, A. L. Colebatch, M. Enders, Á. García-Romero, A. D. Bond, R. García-Rodríguez, D. S.
Wright Dalton Trans. 2018, 47, 7036 – 7043.
[3] S. Hanf, R. García-Rodríguez, S. Feldmann, A. D. Bond, E. Hey-Hawkins, D. S. Wright Dalton Trans.
2017, 46, 814 – 824.
Special Topics
20 12th Australasian Organometallics Meeting
Nineteenth Century Organometallics in Melbourne
Ian D. Rae
Honorary Professorial Fellow, School of Chemistry, University of Melbourne
Australian organometallic chemistry did not begin in Sydney in the 1920s, but at the
University of Melbourne in the late 1880s. Norman Wilsmore, working under the
direction of Professor Masson, made repeated attempts to prepare diethyl
magnesium. These included transmetallation reactions, for which Wilsmore had to
prepare diethyl zinc and diethyl mercury. Extensive discussion of their failures, and
their conclusion that magnesium does not form alkyl derivatives, were reported to the
Chemical Society (London) and the 1891 meeting of the Australasian Association for
the Advancement of Science in Christchurch, New Zealand.
Special Topics
21 12th Australasian Organometallics Meeting
Married at First Sight:
Total Synthesis and Metal Complexes
Mark A. Rizzacasa,* Liselle Atkin, Bill Zongjia Chen, Paul Donnelly, Alex Rafaniello,
Michael Ricca, Angus Robertson and Jonathan M. White
School of Chemistry, The Bio 21 Molecular Science and Biotechnology Institute,
University of Melbourne, Parkville, Victoria, 3010
The total synthesis of natural products is a cornerstone of organic chemistry driving
the development of new reactions and reagents. In addition, total synthesis can be
utilized to confirm structure and provide quantities of rare natural products for further
biological evaluation. Metal mediated reactions, in particular, are often critical in
complex molecule synthesis and some recent targets within the group such as the
citrafungins (revised structures) and the spirodienals have important transformations
that rely on transition metal complexes. This work has led to a new program focused
on the synthesis and application of Mn and Co complexes for the regioselective
hydration of polar alkenes. This presentation will detail our latest results in this area.
OO
(CH2)7CH3
O
HO2C
HO2C
HO2C
O
H
HO
HO2C
HCitrafungin A
(revised structure)
O
OMe
OH
MeO
Me Me
OH
Me
Me
Me
OH
Me Me
CHO
Spirodienal C
Mn Cat., PhSiH3
O2, iPrOH
O OTBDPSOO OTBDPSO
OH80%
MnIII(EtOSALPN)acac
Oral Presentations
22 12th Australasian Organometallics Meeting
A Mechanistically Guided Approach to C-H Bond
Amidation
Alasdair I. McKay,a Weam A. O. Altalhi,a Paul S. Donnelly,a Allan J. Canty,b Richard
A. J. O’Hair*a
a School of Chemistry, University of Melbourne
b School of Physical Sciences, University of Tasmania,
Transition-metal catalysed C-H bond functionalization reactions have emerged as
atom efficient strategies for chemical synthesis by avoiding tedious substrate
preactivation steps and eliminating waste. Whilst C-H arylation and C-H alkyne
insertion reactions have been extensively investigated,[1] related C-H amidation
procedures have received considerably less attention.[2] Amides are a very important
function group widely applied in industry and drug design. Transition metal catalysed
methods to prepare amides have principally employed expensive and precious
rhodium based precatalysts, which are environmentally disadvantageous, especially
for future industrial applications.[3]
In this contribution we develop inexpensive C-H amidation catalysts. We characterise
key intermediates using electrospray ionisation mass spectrometry (ESI-MS). Which
combined with DFT calculations enables a detailed examination of the mechanism of
transition metal catalysed C-H bond amidation.
Figure 1. Metal catalysed insertion of an iso(thio)cyanate into a C-H bond.
References
[1] D. A. Colby, R. G. Bergman, J. A. Ellman, Chem. Rev. 2010, 110, 624-655.
[2] K. D. Hesp, R. G. Bergman and J. A. Ellman, J. Am. Chem. Soc., 2011, 133, 11430-11433.
[3] Y. Park, K. T. Park, J. G. Kim, S. Chang, J. Am. Chem. Soc. 2015, 137, 4534-4542.
Oral Presentations
23 12th Australasian Organometallics Meeting
In-depth study of a Highly Efficient Enantioselective
Intramolecular Hydroamination Reaction
Daven J. Foster, Pengchao Gao, Gellért V. Sipos, Reto Dorta*
School of Molecular Sciences, University of Western Australia
Following the introduction of chiral, cationic NHC-iridium complexes as catalysts for
the intramolecular hydroamination reaction of unactivated alkenes,[1] work has been
put into optimising conditions and obtaining cyclised products beyond the basic
methylated pyrrolidine motif. These new systems require lower catalyst loadings and
milder reaction conditions to produce high yields and optical purities of the cyclised
products, therefore significantly expanding the scope compared to earlier rare-earth
metal and ETM systems.[2] A comparison of catalysts and mechanistic investigations
into the reaction pathway will also be discussed.
Figure 1: Asymmetric iridium catalysed hydroamination reaction involving cyclisation of a variety of
amino olefin substrates
References
[1] a) Sipos, G., Ou, A., Skelton, B.W., Falivene, L., Cavallo, L. and Dorta, R. Chem.: Eur. J.,
2016, 22(20), 6939-6946. b) Gao, P., Sipos, G., Foster, D. and Dorta, R. ACS Catalysis, 2017, 7(9),
6060-6064.
[2] For selected references: a) Wood, M. C.; Leitch, D. C.; Yeung, C. S.; Kozak, J. A.; Schafer, L. L.
Angew. Chem. Int. Ed. 2007, 46, 354. b) Zhang, X.; Emge, T. J.; Hultzsch, K. C. Angew. Chem. Int. Ed.
2012, 51, 394. c) Manna, K.; Eedugurala, N.; Sadow, A. D. J. Am. Chem. Soc. 2015, 137, 425.
Oral Presentations
24 12th Australasian Organometallics Meeting
Theoretical insights into ligand photorelease mechanisms:
new types of 3MC states
Isabelle M. Dixon,a* Adrien Soupart,a Fabienne Alary,a Jean-Louis Heully,a Sylvestre
Bonnet,b Paul I. P. Elliottc
aLaboratoire de Chimie et Physique Quantiques, CNRS/U. Toulouse, France bLeiden Institute of Chemistry, Leiden U., The Netherlands
cDepartment of Chemistry and Center for Functional Materials, U. Huddersfield, UK
The efficiency and selectivity of photoinduced ligand release is key to applications
such as photoactivated chemotherapy (PACT)[1] or light-triggered molecular
machines.[2] Microscopic mechanisms by which this process can be controlled still
require considerable attention and fundamental studies. Bonnet’s group has recently
reported the controlled photorelease of monodentate thioether ligands from Ru(II)
prodrugs.[3] On the other hand, Elliott’s group is interested in the controlled
photorelease of bidentate ligands.[4] In joint experimental-theoretical studies, using a
combination of DFT-based methods, we have shown that the topology of the lowest
triplet excited potential energy surface (3PES) was crucial in the ligand photorelease
efficiency. Different types of original 3MC excited states of peculiar geometries were
proposed to be key to the photorelease mechanisms,[5,6,7] and will be presented here.
References
[1] Gasser et al. Chem. Sci. 2015, 5, 2660. Turro et al. Coord. Chem. Rev. 2015, 282-283, 110.
[2] Credi et al. Eur. J. Inorg. Chem. 2018, 4589 and references therein.
[3] Bonnet et al. Inorg. Chem. 2013, 52, 9456.
[4] Elliott et al. Angew. Chem. Int. Ed. 2013, 52, 10826.
[5] Alary, Bonnet et al. Inorg. Chem. 2016, 55, 4448.
[6] Dixon, Elliott et al. Phys. Chem. Chem. Phys. 2017, 19, 27765.
[7] Dixon, Elliott et al. Inorg. Chem. 2018, 57, 3192.
Oral Presentations
25 12th Australasian Organometallics Meeting
Detection and Reactivity of a Bridging C1 Ligand
Harrison J. Barnett, Anthony F. Hill*
ANU Research School of Chemistry. Australian National University, Sullivans Creek
Road, Acton, ACT, 2601
Monoatomic carbon bridges (-carbido) are notably rare in transition metal chemistry.
When considering μ-carbido complexes, two formal bonding modes are reported; the
symmetric cumulenic (M=C=M), and the asymmetric metallacarbyne (M≡C-M). The
cumulenic bonding mode is scarce in the literature by comparison due to limited
synthetic routes and metal centre electronic requirements.
This work follows on from the synthesis of a simple rhodium cumulenic -carbido
species, [Rh2(-C)Cl2(PPh3)4], which was formed via activation of a thiocarbonyl ligand
with catecholborane.[1] The labile phosphines can be removed under mild conditions
and replaced with bridging bidentate ligands, forming “A-frame” carbido complexes,
such as [Rh2(-C)Cl2(-dppm)2].
Initial reactivity studies of the cumulenic -carbido ligand have provided inter alia the
first structural examples of 2-halocarbyne species with both chlorine and bromine.[2]
Simplified molecular structures of [Rh2(-C)Cl2(-dppm)2] and [Rh2(-C)(-Br)(-CBr)Br4(-dppm)2]
References
[1] H. J. Barnett, L. K. Burt and A. F. Hill, Dalton Trans., 2018, 47, 9570
[2] H. J. Barnett, A. F. Hill, Chem. Commun., 2019, 55, 1734
Oral Presentations
26 12th Australasian Organometallics Meeting
Synthesis and Properties of 2,7-alkynyldihydropyrene
Photochromic Switches
Angus A. Gillespie, Max Roemer, George A. Koutsantonis*
School of Molecular Sciences, The University of Western Australia
The manipulation of single molecules to mimic the properties of electronic circuit
components is the cornerstone of molecular electronics. The dihydropyrene (DHP)
family is a promising example of photochromic switches that under the irradiation of
visible light isomerise to the cyclophanediene (CPD) form that can return to the DHP
form via UV irradiation or heat. The implementation of DHP in molecular circuits
requires a mode of contact between the bridge and electrode, surface contacting
groups.1
Investigation into the conductive properties of DHPs has been limited to functional
substitutions at the 4/5 and 9/10 positions. This presentation will describe the
synthesis of DHPs with alkynyl substituents at the 2/7 positions and their electronic
and photochromic properties (Figure 1). Further functionalisation of these compounds
can promote an alternative conductance pathway and new electronic and
photochromic behaviours can be observed.
Figure 1: Photochromic isomerisation between the DHP (closed) and CPD (open) forms. R = Ethyl,
Butyl
References
[1] Roldan, D.; Kaliginedi, V.; Cobo, S.; Kolivoska, V.; Bucher, C.; Hong, W.; Royal, G.; Wandlowski, T., Charge transport in photoswitchable dimethyldihydropyrene-type single-molecule junctions. J. Am. Chem. Soc. 2013, 135 (16), 5974-7.
TIPS
TIPS
RR
TIPS
TIPS
RRvis.hv
UVhvD
Oral Presentations
27 12th Australasian Organometallics Meeting
Accessing unsupported magnesium 2-aza allyl complexes
Jamie A. Greer, Victoria L. Blair, Phil C. Andrews*
School of Chemistry, Monash University
2-aza allyl amides are a class of organometallic complexes predominantly applied in
[2+3] cycloaddition reactions. They are generally synthesised via deprotonation of
benzylphenylmethanimine derivatives via strong group 1 bases. These compounds
have seen an increase in interest recently due to demonstrations of their capability to
cross couple with aryl halides without the need for heavy metals.[1] Furthermore,
accompanying pyridyl R-groups have been used to form stable complexes using less
electropositive metals, such as aluminium, that are capable of undergoing [3+3]
dimerisation reactions when irradiated with UV light.[2]
Previous research by the Andrews groups have structurally characterised several Na
and K analogues of these systems that can be synthesised through direct
deprotonation, or via a beta-hydride elimination route from dibenzylamine derivatives.
The use of these heavier alkali metal complexes has allowed for favourable
transmetalation with magnesium salts, a feat generally unachievable via alternative
routes, which has been conducted in order to gauge their comparative reactivity. We
will report on some of the [3+3] cyclisation dimerisation observed from these
experiments as well as the unexpected radical behaviour of these species.
Figure 1: Solid state monomer of {[PhC(=CH2)NCH2Ph]2Mg·THF2}
References
[1] M. Li, S. Berritt, L. Matuszewski, G. Deng, A. Pascual-Escudero, G. B. Panetti, M. Poznik, X. Yang,
J. J. Chruma and P. J. Walsh, J. Am. Chem. Soc., 2017, 139, 16327-16333.
[2] S. Suárez-Pantiga, K. Colas, M. J. Johansson and A. Mendoza, Angew. Chem. Int. Ed., 2015, 54,
14094-14098.
Oral Presentations
28 12th Australasian Organometallics Meeting
Switchable Heterometallic Supramolecular Cages
Lynn S. Lisboa, James D. Crowley*
Department of Chemistry, University of Otago
Homodimetallic supramolecular cages, architectures composed of two metal centres
bridged by connecting ligands, have a central cavity that can host guest molecules.1
The cages’ affinity to bind guest molecules can be exploited as potential drug delivery2
and catalytic3 systems. However, a major limitation of supramolecular cages is its
inability to release its guest molecule without complete or irreversible disassembly
upon activation.1b, 4
We aim to synthesise platinum(II)/palladium(II) heterometallic cages capable of guest
release through partial disassembly/reassembly via the addition/elimination of an
external stimulus. We will do so by exploiting the difference in lability between platinum
and palladium.
Figure 1: Proposed assembly and stimulated partial disassembly of a heterometallic PtII/PdII cage.
References
[1] (a) Cook, T. R.; Stang,P. J. Chem. Rev. 2015, 115 (15), 7001-7045; (b) McConnell, A. J.; Wood, C.
S.; Neelakandan, P. P.; Nitschke, J R. Chem. Rev. 2015, 115 (15), 7729-7793.
[2] Zheng, Y. R.; Suntharalingam, K.; Johnstone, T. C .; Lippard, S. J. Chem. Sci. 2015, 6 (2), 1189-
1193.
[3] (a) Martí-Centelles, V.; Lawrence, A. L.; Lusby, P. J. J. Am. Chem. Soc. 2018, 140 (8), 2862-2868;
(b) Ueda, Y.; Ito, H.; Fujita, D.; Fujita,M. J. Am. Chem. Soc. 2017, 139 (17), 6090-6093.
[4] Kim, T. Y.; Vasdev, R. A. S.; Preston, D.; Crowley, J. D. Chem. Eur. J. 2018, 24 (56), 14878-14890.
Oral Presentations
29 12th Australasian Organometallics Meeting
Beryllium
Albert Paparo, Cameron Jones*
School of Chemistry, Monash University
Fear of death and injury is a blessing and at the same time a great obstacle for
chemists. While keeping us alive, it also limits the resources invested into research on
explosive, radioactive, highly toxic or otherwise dangerous materials. Beryllium is
considered to be one of the most toxic elements, hence its chemistry has been left
mostly unexploited.[1] Curiosity has trumped our drive for self-preservation, and we are
exploring the basic chemistry of reactive beryllium species.
The reason for our interest is that there are now numerous examples of low-valent
main-group metal compounds that are capable of activating environmentally relevant
small molecules such as CO2 in a transition-metal-like fashion.[2] The s block is
represented by the Mg–Mg bonded dimers and their rich reactivity with small
molecules.[3] However, low-valent Be or Ca complexes are confined to single
examples.[4] Here, we reveal the very first Al–Be bonded species. A collection of
curiosities generated along the track will be also presented (see Scheme 1).
Scheme 1. Al–Be species and other curiosities.
References
[1] D. Naglav, M. R. Buchner, G. Bendt, F. Kraus, S. Schulz, Angew. Chem. Int. Ed. 2016, 55, 10562-
10576.
[2] a) P. P. Power, Chem. Rev. 1999, 99, 3463-3504; b) P. P. Power, Nature 2010, 463, 171-177; c) T.
Chu, G. I. Nikonov, Chem. Rev. 2018, 118, 3608-3680.
[3] a) S. P. Green, C. Jones, A. Stasch, Science 2007, 318, 1754-1757; b) C. Jones, Nat. Rev. Chem.
2017, 1, 0059.
[4] Be(0): a) M. Arrowsmith, H. Braunschweig, M. Celik, T. Dellermann, R. D. Dewhurst, W. C. Ewing,
K. Hammond, T. Kramer, I. Krummenacher, J. Mies, K. Radacki, J. K. Schuster, Nat. Chem. 2016,
8, 890–894; b) G. Wang, L. Freeman, D. Dickie, R. Mokrai, Z. Benkő, R. Gilliard, Chem. Eur. J.
2019, 25, 4335-4339. Ca(I): S. Krieck, H. Gorls, L. Yu, M. Reiher, M. Westerhausen, J. Am. Chem.
Soc. 2009, 131, 2977-2985.
N
N
tButBu
Be Br
BeN
N
tBu
tBuBe
Br
N
NtBu
tBu
BeBr
Be
H
H
H
H
N
N
tBu
tBuBe
Br
H
H
H
H*
*
Li
NMe2
Me2N
CH3
Be
H3C
CH3
Li
NMe2
Me2NH3
CN
N
Dip
Dip
Al Be
Hal
Hal
N
N
Hal = Br, I
Dip = 2,6-iPr2C6H3
Oral Presentations
30 12th Australasian Organometallics Meeting
Porphyrins and Electron-Rich Alkynyl Complexes: A Step
toward Remarkable Redox-active Molecular Arrays for
Electronics or Photonics
Frédéric Paul
Univ Rennes, CNRS, ISCR, UMR 6226, F-35000 Rennes (France)
Tetra-arylporphyrins constitute appealing redox-active molecular platforms endowed
with interesting linear and nonlinear optical properties. When associated to electron-
rich alkynyl complexes, used as redox-switchable electron-releasing groups, the
resulting molecules can often present remarkable properties for developing molecular-
based devices for electronics or photonics.[1] Through several examples, we will
present our work in this field based on various families of derivatives always
associating simple porphyrin cores and various metal alkynyl complexes. Initially
focussed on the development of molecular wires such as 1+,[2] we will show how we
evolved toward the design of nonlinear electrochromes such as 2,[3] for instance,
before finally attempting to design redox-switchable luminophores such as 3 (Fig. 1),
the latter prospect turning out to be much more challenging than initially expected.
More interesting than the design and synthesis of these particular targets, we hope to
show that a proper understanding of the interplay between electron transfer and
photonic properties at the molecular level can lead to the design of new organometallic
molecules endowed with outstanding properties and tailored for addressing some of
the societal challenges of the future.
Fig 1. Some derivatives that will be discussed.
References
[1] (a) Marques-Gonzales, S.; Low, P. J. Aust. J. Chem. 2016, 69, 244. (b) Grelaud, G.; Cifuentes, M.
P.; Paul, F.; Humphrey, M. G. J. Organomet. Chem. 2014, 751, 181.
[2] Malvolti, F.; Le Maux, P.; Toupet, L.; Smith, M. E.; Man, W. Y.; Low, P. J.; Galardon, E.; Simonneaux,
G.; Paul, F. Inorg. Chem. 2010, 49, 9101.
[3] Merhi, A.; Grelaud, G.; Morshedi, M.; Abid, S.; Green, K. A.; Barlow, A.; Groizard, T.; Kahlal, S.;
Halet, J.-F.; Ngo, H. M.; Ledoux-Rak, I.; Cifuentes, M. P.; Humphrey, M. G.; Paul, F.; Paul-Roth, C. O.
Dalton Trans. 2018, 47, 11123.
Oral Presentations
31 12th Australasian Organometallics Meeting
Extending Alkali Metal Mediated Magnesiation from
nitrogen to phosphorus
Michael A. Stevens, Phil C. Andrews, Victoria L. Blair*
School of Chemistry, Monash University
Metalation chemistry has been dominated by the alkyl lithiums and lithium secondary
amides.[1] In comparison to the wealth of knowledge on nitrogen based metalation
chemistry, there has been comparatively few studies on their heavier group 15
phosphorus analogues.[2,3] The electronic properties conferred on compounds by the
heavier elements can differ dramatically from the lighter ones.
Herein we report a comparative reactivity study of homologous nitrogen and
phosphorus based compounds with the sodium magnesiate complex
[(TMEDA)Na(TMP)2Mg(CH2SiMe3)]. These new bi-metallic bases are synergic
reagents combining the reactivity of an alkali metal with a less reactive metal, such as
magnesium or zinc. These bases have been found to react with unique
regioselectivity, as well as allowing mild reaction conditions. X-ray crystallography
structural studies, solution state NMR studies and electrophilic quenches studies will
be presented.
Scheme 1: The reaction of the sodium magnesiate base with P,P-diisopropylphenylphosphine, resulting
in the meta-magnesiated compound [(TMEDA)Na(TMP)(m-iPr2PC6H4)Mg(TMP)]
References
[1] R. E. Mulvey, Acc. Chem. Res. 2009, 42, 743–755.
[2] V. L. Blair, M. A. Stevens, C. D. Thompson, Chem. Commun. 2016, 52, 8111–8114.
[3] M. A. Stevens, F. H. Hashim, E. S. H. Gwee, E. I. Izgorodina, R. E. Mulvey, V. L. Blair, Chem. - A Eur. J. 2018, 24, 15669–15677.
Oral Presentations
32 12th Australasian Organometallics Meeting
Sodium-magnesiate facilitated cyclisation of imines via C-F
bond activation
Samantha A. Orr, T. Wollmann, Phil C. Andrews* and Victoria L. Blair*
School of Chemistry, Monash University, Clayton, Melbourne, Victoria, 3800
Imines are valuable building blocks for the synthesis of many complex molecules due
to their simple preparation. Applications of Schiff’s bases include ligands for metal-
complexation, preparation of amines and precursors for pharmaceutical scaffolds. Due
to their importance, efforts to develop new functionalisation methods are ongoing. A
concurrent interest we have is the synthetic design of fluorinated substrates, owing to
their medicinal relevance with a C-F bond appearing in 20% of new drugs.1 Transition
metals have generally dominated the field of C-F activation2 but more recently s-block
and low valent species have showed success.3
The work presented will focus on synthetic transformations of fluoro-substituted imines
employing our sodium-magnesiate bimetallic base and the monometallic counterparts.
Initial studies revealed a selective ortho-C-F activation of a pentafluoro-substituted aryl
imine, leading to the unprecedented cyclisation of two imine species (figure 1). The
resultant novel 8-membered carbon-nitrogen ring has been fully characterised by x-
ray crystallography and NMR spectroscopy, the scope has been extended and the
mechanistic pathway probed.
Figure 1: Reaction of pentafluoro-arylimine and sodium-magnesiate mediated C-F activation.
References
[1] K. Müller, C. Faeh, F. Diederich, Science, 2007, 317, 1881. [2] T. Fujita, K. Fuchibe, J. Ichikawa,
Angew. Chem. Int. Ed., 2019, 58, 390. [3] F. M. García-Valle, V. Tabernero, T. Cuenca, M. E. G.
Mosquera, J. Cano, Organometallics, 2019, 38, 894; C. Bakewell, A. J. P. White, M. R. Crimmin, J. Am.
Chem. Soc., 2016, 138, 12763.
Oral Presentations
33 12th Australasian Organometallics Meeting
Tris(styryl)isocyanurates: Towards New Dyes with Large Two-Photon Absorption Cross-Sections
Alphonsine NGO NDIMBA1,2, Amédée TRIADON1,2, Nicolas RICHY2, Mahbod
MORSHEDI1, Marie P. CIFUENTES1, Olivier MONGIN2, Frédéric PAUL2 and Mark
G. HUMPHREY1*
1Research School of Chemistry, Australian National University, Canberra, ACT 2601
(Australia)
2Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de
Rennes, Campus Beaulieu, 35042 Rennes Cedex (France)
Materials possessing third-order nonlinear optical properties have recently aroused
considerable interest due to potential applications in areas such as optical
limiting[1].1,3,5-Triaryltriazinanes-2,4,6-triones (1-X, more commonly known as
triphenylisocyanurates) have been reported by some of us as exhibiting remarkable
optical properties[2]. When Ru-alkynyl complexes ([Ru] = Ru(dppe)2) are appended in
place of the X substituents, the organometallic end groups enhance tremendously the
two-photon absorption cross-sections in compounds such as 1 compared to extended
all-organic 1-X analogues functionalized by electron-releasing X substituents (X =
NMe2) [2]. We were therefore curious to investigate the effect of this substitution in a
more conjugated tris(styryl) analogue. Accordingly, we will report herein the synthesis
of a family of tris(styryl)isocyanurates and our attempts to isolate the tris(styryl)
analogue of 1-X.
N
N
N
N
N
N
N
N
N
O
O OO
O O
O
O O
X X
X
X X
X
Ru
RuRuClCl
Cl1-X
12-X
Ru = RuPPh2Ph2P
PPh2Ph2P
References
[1] (a) G.S. He; L.-S. Tan; Q. Zheng; P.N. Prasad Chem. Rev. 2008, 108, 1245; (b) M. Pawlicki; H.A.
Collins; R.G. Denning; H.L. Anderson Angew. Chem. Int. Ed. 2009, 48, 3244 – 3266.
[2] G. Argouarch; R. Veillard; T. Roisnel; A. Amar; H. Meghezzi; A. Boucekkine; V. Hugues; O. Mongin;
M. Blanchard-Desce; F. Paul Chem. Eur. J. 2012, 18, 11811-11827.
Oral Presentations
34 12th Australasian Organometallics Meeting
Nucleophilic aluminium: Synthesis, structural and reaction
chemistry of the aluminyl anion
Jamie Hicks,a,b Jose M. Goicoecheab,* and Simon Aldridgeb,*
aResearch School of Chemistry, Australian National University, 2601
bChemistry Research Laboratory, 12 Mansfield Road, University of Oxford, OX1 3TA
Aluminium is the most abundant metal in the Earth’s crust and is widely exploited in a
number of key industrial processes. Being located in group 13 of the Periodic Table it
possesses four valence orbitals but only three valence electrons. Its reactivity is
therefore dominated by its electron deficiency and electropositivity: Al(III) compounds
are archetypal electrophiles. Last year, we reported that anionic Al(I) compounds can
act as nucleophiles, with the dimethylxanthene-stabilized potassium aluminyl
compound [K{(NON)Al}]2.[1] The complex has been shown to react in an
unprecedented ‘umpolung’ fashion as an aluminium-centred nucleophile in the
formation of a range of Al-E covalent bonds (E = H, C or metals), including in the
synthesis of the first nucleophilic gold compound [(NON)AlAuPtBu3].[2]
More recently, it has been found that by adding the potassium sequestering reagent
2.2.2-cryptand to the dimeric aluminyl complex, the first ‘naked’ aluminyl species of
the type [K(2.2.2-crypt)][(NON)Al] can be synthesised. This complex shows
remarkable reactivity towards aromatic molecules, for example inserting into the C-C
bond of benzene to give the 7-membered heterocycle [K(2.2.2-crypt)][(NON)AlC6H6]
(Figure 1).[3] This C-C bond activation of benzene was found to be reversible;
mechanistic details and functionalisation of the C-C bond activation will be discussed.
Figure 1. C-C bond activation of benzene by a monomeric aluminyl complex.
References
[1] J. Hicks, P. Vasko, J. M. Goicoechea, S. Aldridge, Nature, 2018, 557, 92–95.
[2] J. Hicks, Akseli Mansikkamäki, P. Vasko, J. M. Goicoechea, S. Aldridge, Nature Chemistry, 2019,
11, 237–241.
[3] J. Hicks, P. Vasko, J. M. Goicoechea, S. Aldridge, submitted.
Oral Presentations
35 12th Australasian Organometallics Meeting
New aluminium lanthanoid biphenolate complexes through
redox transmetallation protolysis
Angus C. G. Shephard,a Safaa H. Ali,a Glen B. Deacon,b Peter C. Junka
a College of Science and Engineering, James Cook University, Townsville Qld 4811,
Australia
b School of Chemistry, Monash University, Clayton Vic 3800, Australia
Carbon-bridged biphenol ligands have garnered significant attention in the field of
organometallic chemistry, particularly as lanthanoid biphenolate complexes. This
interest has stemmed from their ability to catalyse a range of organic transformations.
Access to these lanthanoid biphenolate complexes has typically been achieved via
ligand exchange reactions, involving treating the corresponding LnCpx, or
Ln{N(SiMe3)2}x with the desired biphenol ligand.1,2 An alternative, and much neglected,
synthesis of these complexes is afforded by redox transmetallation/protolysis (RTP)
(Scheme 1). These lanthanoid biphenolate complexes display further reactivity
towards metal alkyl reagents, forming both ionic, and non-ionic heterobimetallic
complexes. These new heterobimetallic complexes are expected to be active catalysts
for the ring opening polymerisation of rac-lactide. Herein, the synthesis and
characterisation of some heterobimetallic biphenolate complexes is described.
Scheme 1 – Synthesis of carbon-bridged biphenolate lanthanoid complexes by redox transmetallation protolysis, and subsequent metallation by trimethyl aluminium
References
(1) Deng, M.; Yao, Y.; Shen, Q.; Zhang, Y.; Sun, J. Dalt. Trans. 2004, 4, 944–950
(2) Qi, R.; Liu, B.; Xu, X.; Yang, Z.; Yao, Y.; Zhang, Y.; Shen, Q. Dalt. Trans. 2008, 7, 5016–5024
Oral Presentations
36 12th Australasian Organometallics Meeting
Synthesis of ruthenium diimine complexes for catalysis
Jeremy Stone1, Mark Spackman1, Paul Low1, George Koutsantonis1*
1 School of Molecular Sciences, The University of Western Australia
Converting small molecules such as CO2 and N2 to higher value products generally
requires the use of a transition metal catalyst. This work describes the synthesis of a
variety of organometallic complexes containing diimine ligands, which can be easily
modified to change the properties of the complex to be beneficial for such catalysis.
Starting from a versatile ruthenium naphthalene starting material (Fig. a) a range of
complexes can be reached with different steric, electronic and solubility properties.1
Examples include sterically hindered diimine ligands (Fig. b) and highly fluorous
ligands that could allow for homogeneous catalysis in supercritical CO2.2 The reactivity
of these complexes has been developed to show hydride and acetylide complexes
can be reached. Isolating hydride complexes is important for activating CO2 as it allows
for insertion into the metal hydride bond.3
a) b)
Figure a) General synthesis of ruthenium diimine complexes. Figure b) Crystal structure of sterically
hindered ruthenium diimine complex.
References
1. Stone, J.; Jago, D.; Sobolev, A.; Spackman, M.; Koutsantonis, G., Aust. J. Chem. 2018, 71 (4), 289-294.
2. Berven, B. M.; Koutsantonis, G. A.; Skelton, B. W.; Trengove, R. D.; White, A. H., Dalton Trans. 2011,
40 (16), 4167-4174.
3. Sordakis, K.; Tang, C.; Vogt, L. K.; Junge, H.; Dyson, P. J.; Beller, M.; Laurenczy, G., Chem. Rev. 2018,
118 (2), 372-433.
Oral Presentations
37 12th Australasian Organometallics Meeting
Exploring properties of novel Ga(III) and Bi(III) flavonolate
complexes
Kirralee J. Burke, Victoria L. Blair, Phil C. Andrews*
School of Chemistry, Monash University
Flavonols (3-hydroxyflavones) are widely researched due to their ubiquitous presence
in dietary plants and their well-demonstrated in vitro anti-oxidant, anti-bacterial, and
anti-cancer properties.[1] While flavonols contain a facile O,O metal-chelating site
through the alpha-hydroxy ketone moiety, metal-flavonolate complexes remain
uncommon and examples are greatly limited to transition metals.[2]
Here we present the first examples of gallium(III) and bismuth(III) flavonolate
complexes. The in vitro biological activity of these compounds towards mammalian
and bacterial cells will be discussed. The luminescent properties of these novel
complexes will also be presented. Dimethylgallium flavonolate derivatives such as
[Ga(CH3)2(4DMAF)] (Figure 1) have been found to be highly emissive in both the solid
state and in solution, and their respective photophysical properties can be tuned by
altering the substituents on the flavonolate ligand.
Figure 1. Molecular structure of dimethylgallium(III) flavonolate complex [Ga(CH3)2(4DMAF)].
References
[1] A. Y. Chen, Y. C. Chen, Food Chem. 2013, 138, 2099.
[2] M. M Kasprzak, A. Erxleben, J. Ochocki, RSC Adv. 2015, 5, 45853.
Oral Presentations
38 12th Australasian Organometallics Meeting
Caught at Last! Isolation, Structural Characterization and
Gas-phase Studies of the [Ag10(H)8L6]2+ Nanocluster
Dication
Howard Z. Ma,* Alasdair I. McKay,* Jonathan M. White,* Roger J. Mulder,† A.
Mravak,‡ Michael Scholz,* Gavin E. Reid,* Evan J. Bieske,* Vlasta Bonačić-
Koutecký,‡ Richard A. J. O’Hair*
*School of Chemistry, University of Melbourne, Australia
†Biophysics Group, CSIRO Manufacturing, Australia
‡Interdisciplinary Center for Advanced Sciences and Technology, University of Split,
Croatia
Coinage metal nanoclusters (CMNs) continue to attract attention as models for
nanoparticles, for their structure and bonding arrangements, spectroscopic properties
and roles in catalysis. We have been using an approach that blends electrospray
ionization mass spectrometry (ESI-MS) to direct the bulk synthesis of CMNs, X-ray
crystallography, neutron diffraction and NMR spectroscopy for structural
characterization, and multistage mass spectrometry (MSn) experiments in conjunction
with Density Functional Theory (DFT) calculations to examine the chemistry of CMNs.
The [Ag10(H)8L’6]2+ cluster dication is observed to be a major ion in the ESI-MS
solutions containing a silver salt (AgBF4), the small bite angle bisphosphine ligand L’
= DPPM = bis(diphenylphosphino)methane and sodium borohydride (NaBH4). Like
the Scarlett Pimpernel, it has eluded capture for X-ray crystallographic
characterization. Our previous efforts at characterizing its structure employed VUV
photoionization in conjunction with DFT to predict a silver cluster core with a bicapped
square antiprism (J17) structure.[1]
Here, we present a new chapter in this story of this decanuclear cluster. During recent
efforts at preparing and studying the reactions of [Ag3(H)(BH4)L3](BF4), where L =
DPPA = bis(diphenylphosphino)amine, we noticed the formation of colored crystalline
material that turned out to be salts of the related [Ag10(H)8L6]2+ cluster dication.
Gratifyingly, X-ray crystallography revealed the same Ag10 core with a bicapped
square antiprism (J17) structure, although with a different arrangement of the
bisphosphine ligands. Attempts to link the solid-state, solution-phase and gas-phase
structure of [Ag10(H)8L6]2+ will be presented and reactions with relevant
heterocumulenes including CS2 and thiocyanates will be further explored.
References
[1] S. Daly, M. Krstić, A. Giuliani, R. Antoine, L. Nahon, A. Zavras, G. N. Khairallah, V. Bonačić-
Koutecký, P. Dugourd, R. A. J. O’Hair, Phys. Chem. Chem. Phys., 2015, 17, 25772
Oral Presentations
39 12th Australasian Organometallics Meeting
From Reactor to Radiotracer at ANSTO - Increasing the
Availability of Non-routine Radionuclides
Margaret Aulsebrooka*, Leena Hogana, Tom Cresswella, Grant Griffithsa, Attila
Stopica, Ivan Gregurica, Paul Pellegrinia.
aANSTO, New Illawarra Rd, Lucas Heights, NSW 2234, Australia.
Increasing the range and accessibility of radioisotopes is a key objective of the
radioisotopes research team at ANSTO, contributing to the ANSTO Health Strategy
and aligning with ANSTO’s role within the NCRIS National Imaging Facility. The team
has significant experience in the production, separation, purification, characterisation
and formulation of radioisotopes for medical research. Accomplishments include the
development of a (68Ge)/(68Ga) generator for PET imaging,[1-2] the neutron irradiation
and subsequent separation of 177Lu from Yb targets[3-5] and in the high through-put
conversion of (67Ga) gallium citrate to (67Ga) gallium chloride used in phase one clinical
trials targeting prostate cancer.
This talk follows the recent achievements of the radioisotopes team in the delivery of
niche radionuclides to the broader scientific community for the development of new
technologies in medicine, environmental science and fundamental research. Recent
work in the production of non-routine reactor based radioisotopes will be highlighted
with a focus on the therapeutic radionuclide scandium-47 which has recently been
achieved using the OPAL nuclear reactor. Overall, a summary of ANSTO’s recent
efforts to improve access to radioisotopes and radiotracers will be provided along with
a discussion of where this exciting research is heading in the immediate future.
References
[1] Van So, L.; Izard, M.; Pellegrini, P.; Zaw, M., Development of 68Ga Generator at ANSTO: 1st World
Congress on Ga-68 and Peptide Receptor Radionuclide Therapy, THERANOSTICS, Bad Berka,
Germany, June 23-26, 2011, P-023.
[2] Le V.S., 68Ga Generator Integrated System: Elution–Purification–Concentration Integration. In
Theranostics, Gallium-68, and Other Radionuclides. Recent Results in Cancer Research Vol. 194 (eds.
Baum R., Rösch F.) 43-75 (Springer-Verlag, Berlin, Heidelberg 2013).
[3] Van So, L.; Morcos, N., New SPE column packing material: Retention assessment method and its
application for the radionuclide chromatographic separation. Journal of Radioanalytical and Nuclear
Chemistry 2008, 277 (3), 651.
[4] Van So, L.; Morcos, N.; Zaw, M.; Pellegrini, P.; Greguric, I., Alternative chromatographic processes
for no-carrier added 177Lu radioisotope separation Part I. Multi-column chromatographic for clinically
applicable. Journal of Radioanalytical and Nuclear Chemistry 2008, 277 (3), 663.
[5] Van So, L.; Morcos, N.; Zaw, M.; Pellegrini, P.; Greguric, I., Nevissi, A., Alternative
chromatographic process for no-carrier added 177Lu radioisotope separation. Part II. The
conventional column chromatographic separation combined with HPLC for high purity. Journal of
Radioanalytical and Nuclear Chemistry 2008, 277(3), 675.
Oral Presentations
40 12th Australasian Organometallics Meeting
Robust and Recyclable Hybrid Rhodium- and Iridium-
Catalysts with Long Alkyl Tethers
Max Roemer1, Vinicius R. Goncales2, Mohan Bhadbhade2, Barbara A. Messerle1*
1Macquarie University, NSW 2109, Australia, 2 UNSW, NSW 2052, Australia
Transition-metal catalysis is ubiquitous in synthetic chemistry and is among the most
important processes in the chemical industry. Surface immobilised transition metal
catalysts are known as hybrid catalysts as they combine the efficiency of
heterogeneous- and the selectivity of homogenous catalysts. Advantages to the
traditional homogeneous analogues are stability and simplified removal of the catalyst
from the reaction mixture, which provides access to urgently needed more efficient
and greener processes.[1] Here, we present a series of new hybrid Rh- and Ir-based
pyrazole-triazole complexes attached to carbon black (CB) with varying tether length.
The catalysts are composed of a surface anchoring group, an alkyl linker and the
catalytically active metal complex as head group. The synthesis was accomplished
through the high yield alkyl group introduction to aromatic systems[2,3], Click-chemistry
and finally, metal coordination. The length of the alkyl linker (n = 5, 10) was varied to
probe its influence on the catalytic activity. We immobilised the Ir- or Rh-catalysts on
CB using radical methodology. Initially, we optimised grafting conditions to achieve a
dense packing. Furthermore, we attached both, Rh- and Ir-catalysts, in equimolar
amounts simultaneously to achieve a mixed layer. We analysed the modified surfaces
by SEM, EDS and XPS. Subsequently, we tested the systems in an intramolecular
hydroamination reaction. All hybrids are efficient catalysts, which are robust and
recyclable. Intriguingly, the mixed Rh- and Ir-systems perform significantly better than
the monometallic ones, which was already observed for short-chain analogues.[4] We
are currently investigating the origin of this effect.
Fig. 1. a) A mixed Rh- and Ir-hybrid catalyst, b) Intramolecular hydroamination reaction as model
reaction for testing of the hybrid catalysts, c) Molecular structure derived from X-ray single crystal
diffraction of a long alkyl chain ligand.
References:
[1] Wong et al. Chem. Sci. 2016, 7, 1996–2004.
[2] Chen & Roemer et al. Nature Nanotech. 2017, 12, 797–803.
[3] Roemer et al. Eur. J. Inorg. Chem. 2016, 1314–1318.
[4] Binding et al. Organometallics 2019, 38 (4), pp 780–787.
a) b)
c)
N
N N
N
N
O
Rh
n
Carbon Black (CB)
CO
CO
N
N N
N
N
O
Ir
n
Cp*
Cl
NH2
toluene120 °C
NH
catalyst
OH OHhybrid
Oral Presentations
41 12th Australasian Organometallics Meeting
An Exploration into the synthesis and microbial activity of
some heterocyclic bismuth-based complexes
Sarmishta Munuganti*, Philip C. Andrews, Melissa Werrett
School of Chemistry, Monash University
Over the last 20 years, the emergence of opportunistic microbial pathogens within
hospital environments has increased the incidence of bloodstream infections, primarily
in immunocompromised individuals.[1],[2] The triazole class of compounds have been
shown to display biological activity against fungal infection and are thus a continuing
area of research interest.
General scheme for the synthesis of novel tris- Bi(III)-1,2,4-triazoles derived from thiones.
The potential of binding these molecules to a bismuth metal centre has been explored
to enhance the biological activity of the ligand(s). A series of novel bismuth(III)-1,2,4-
triazole complexes derived from the general structures 5-(Pyridin-4-yl)-4-phenyl-2H-
1,2,4-triazole-3(4H)-thione have been synthesised.
These complexes have been characterised using 1H NMR and 13C NMR spectroscopy,
IR, ESI-MS and elemental analysis. Fungal testing against the strains saccharomyces
cerevisiae (S. cerevisiae) and candida albicans (C. albicans) are currently underway.
References
[1] M. K. Kathiravan, A. B. Salake, A. S. Chothe, P. B. Dudhe, R. P. Watode, M. S. Mukta and S. Gadhwe, Bioorganic Med. Chem., 2012, 20, 5678–5698.
[2] G. Morace, F. Perdoni and E. Borghi, J. Glob. Antimicrob. Resist., 2014, 2, 254–259.
Oral Presentations
42 12th Australasian Organometallics Meeting
A convenient method for the generation of [Rh(PNP)]+ and
[Rh(PONOP)]+ fragments: reversible formation of
vinylidene derivatives
Matthew R. Gyton, Thomas M. Hood, Adrian B. Chaplin*
Department of Chemistry, University of Warwick, UK
Rigid mer-tridentate “pincer” ligands are a prominent ligand class in organometallic
chemistry and catalysis, conferring thermal stability and enabling a wide range of
metal-based reactivity.[1] Pyridinyl-based phosphine variants, 2,6-bis(di-tert-
butylphosphinomethyl)pyridine and 2,6-bis(di-tert-butylphosphinito)pyridine, in
particular have proven to be versatile ligands and have been employed widely in
homogenous catalysis. Herein we report an operationally simple method for the
generation of reactive formally 14 VE rhodium(I) derivatives (1A) of these ligands in
solution, exploiting substitution reactions of [Rh(COD)2][BArF4] in the weakly
coordinating solvent 1,2-C6H4F2.[2] Application of this methodology enables the
synthesis of known adducts of CO, N2, H2, previously unknown water complexes, and
novel vinylidene derivatives [Rh(pincer)(CCHR)][BArF4] (R = tBu, 3,5-tBu2C6H3),
through reversible reactions with terminal alkynes.[3]
Figure 1. Phosphine-based pincer complexes of rhodium (X = O, CH2)
References
[1] a) D. Morales-Morales, C. G. M. Jensen, Eds., The Chemistry of Pincer Compounds, Elsevier,
Amsterdam, 2007. b) G. van Koten, D. Milstein, Eds., Organometallic Pincer Chemistry, Springer Berlin
Heidelberg, Berlin, 2013.
[2] S. D. Pike, M. R. Crimmin, A. B. Chaplin. Chem. Commun., 2017, 53, 3615–3633.
[3] M. R. Gyton, T. M. Hood, A. B. Chaplin, Dalton Trans., 2019, 48, 2877–2880.
Oral Presentations
43 12th Australasian Organometallics Meeting
Heteroatom-Bridged Transition-Metal Carbynes
Benjamin J. Frogley, Anthony F. Hill*
Research School of Chemistry, Australian National University
Transition-metal carbyne complexes, LnM≡CR, have historically been limited to
examples bearing hydrocarbyl (R = alkyl, aryl, etc.), amino or silyl substituents, a
consequence of the classical synthetic pathways not being extendable to the rest of
the p-block.1 Synthetic challenges notwithstanding, there is a strong incentive to
investigate such compounds due to their potentially useful synthetic, electronic and
physical properties which may be modified by the choice of p-block substituent.
Lalor’s bromocarbynes [M(≡CBr)(CO)2(Tp*)] (M = Mo, W; Tp* = hydrotris(3,5-
dimethylpyrazol-1-yl)borate)2 have proven to be useful precursors to such species.
Derivatives can be prepared not only by simple nucleophilic halide substitution, but
also by initial treatment with nBuLi to generate lithiocarbyne intermediates,
[M(≡CLi)(CO)2(Tp*)], which can subsequently react with suitable electrophiles. This
latter procedure allowed the first examples of carbynes with ‘heavy-metalloid’ lead,3
antimony and bismuth substituents4 to be prepared. Extension of this chemistry can
give rise to polymetallic derivatives5 which may serve as useful building blocks for
extended frameworks or interrupted molecular wires. This has particularly interesting
consequences for intermetallic electronic communication where the heteroatoms may
serve as modulators or ‘switches’ in such structures.
References
1. (a) E. O. Fischer, G. Kreis, C. G. Kreiter, J. Müller, G. Huttner and H. Lorenz, Angew. Chem. Int.
Ed., 1973, 12, 564-565; (b) R. R. Schrock, Chem. Commun., 2005, 2773-2777.
2. F. J. Lalor, T. J. Desmond, G. M. Cotter, C. A. Shanahan, G. Ferguson, M. Parvez and B. Ruhl, J.
Chem. Soc., Dalton Trans., 1995, 1709-1726.
3. R. L. Cordiner, A. F. Hill, R. Shang and A. C. Willis, Organometallics, 2011, 30, 139-144.
4. B. J. Frogley and A. F. Hill, Chem. Commun., 2018, 54, 2126-2129.
5. (a) B. J. Frogley and A. F. Hill, Chem. Commun., 2018, 54, 7649-7652; (b) B. J. Frogley and A. F.
Hill, Chem. Commun., 2018, 54, 12373-12376.
Oral Presentations
44 12th Australasian Organometallics Meeting
Multifunctional Cyclopentadiene Ligands for Theranostic
Approaches with Re and 99mTc
Angelo Freia, Roger Albertob*
aInsitute for Molecular Bioscience, The University of Queensland, Australia
b Department of Chemistry, University of Zurich, Switzerland
The ability to manipulate molecules and their properties at will has been scientists
dream since the dawn of chemistry. Particularly in the field of medicinal chemistry it
has been shown again and again, that very small changes can have a dramatic impact
on the biological behaviour of a lead compound. 99mTc is one of the staple
radionuclides for SPECT imaging in the clinic, being used in over 80% of all diagnostic
nuclear imaging studies.1 This is mainly due to the artificial elements favourable
properties and its widespread availability at modest cost. However, current 99mTc
tracers lack the high degree of target specificity that is desired in today’s clinical
applications. Using the cyclopentadiene (Cp) synthon, we have developed a synthetic
approach to multifunctional Cp-Re/99mTc complexes. In this system, the targeting, as
well as other physical and chemical properties of the system can be manipulated
before and after coordination to the metal center. We will report on the chemical
flexibility of this approach as well as the mono- and bi-functionalization of these Cp-
ligands with the synthesis of their respective Re/99mTc complexes. Finally, we will show
how we have used this synthetic toolkit for both conjugated and integrated approaches
preparing new potential theranostic agents with Re and 99mTc.
References
[1] I. Amato, Chem. Eng. News 2009, 87, 58–64. [2] C. Kluba and T. Mindt, Molecules 2013, 18, 3206. [3] A. Frei, B. Spingler, R. Alberto, Chem. Eur. J. 2018, 24, 10156.
Oral Presentations
45 12th Australasian Organometallics Meeting
Palladium-Catalyzed Decarbonylative Trifluoromethylation
of Acid Fluorides
Sinead T. Keaveney†‡ and Franziska Schoenebeck†*
†Institute of Organic Chemistry, RWTH Aachen University, Germany ‡Current: Department of Molecular Sciences, Macquarie University, Australia
Carboxylic acids, and their derivatives, are attractive functionalities for synthetic
manipulations due to their abundance and low cost, and as they can be obtained from
sustainable resources.[1] To further utilize these feedstock chemicals there is a need
to develop strategies to convert carboxylic acids into high value functional groups, with
fluorine being of particular interest due to the numerous applications of organo-fluorine
compounds in the pharmaceutical and agrochemical industries. Further, the
introduction of CF3 via Pd(0)/Pd(II) catalysis is one of the greatest challenges in the
cross-coupling arena due to: i) the difficult reductive elimination of Ar-CF3 from Pd(II);
and ii) the challenging transmetalation of CF3 requires F- additives which can cause
ligand displacement, catalyst decomposition and over-trifluoromethylation.[2] In this
work[3] we overcame these challenges by developing the first protocol to convert acid
fluorides to aryl-CF3, with the key Pd(II)-F intermediate facilitating selective and
additive-free transmetalation, allowing the first use of Xantphos in catalytic
trifluoromethylation. Our computational and experimental reactivity data support a
transmetalation then decarbonylation mechanism.
References
[1] a) R. Takise, K. Muto, J. Yamaguchi, Chem. Soc. Rev. 2017, 46, 5864; b) N.Rodrguez, L. J.
Goossen, Chem. Soc. Rev. 2011, 40, 5030
[2] V. V. Grushin, W. J. Marshall, J. Am. Chem. Soc. 2006, 128, 4632; V. V. Grushin, W. J. Marshall, J.
Am. Chem. Soc. 2006, 128, 12644; Tomashenko, O. A.; Grushin, V. V., Chem. Rev. 2011, 111, 4475;
M. C. Nielsen, K. J. Bonney, F. Schoenebeck, Angew. Chem. Int. Ed. 2014, 53, 5903
[3] Keaveney, S. T.; Schoenebeck, F., Angew. Chem. Int. Ed. 2018, 57, 4073
§ Intramoleculer Pd(II)-F generation
§ Direct transmetalation: no ligand
displacement or over-trifluoromethylation
§ First catalytic effectiveness of Xantphos § Decarbonylation from PhCO-[Pd(II)]-CF3
more facile than that from PhCO-[Pd(II)]-F
17.4 kcal mol-1
27.3 kcal mol-1
Pd
O Ph
CF3PP
Pd
OPh
FP
P
Pd
O Ph
CF3PP
Pd
OPh
FP
P
vs
via:
PdCF3
ArPd
CF3
Ar
O
CO
F
O
R
CF3
R
[Pd(0)]/Xantphos
TESCF3K3PO4 (0.2 eq.)
P
P
P
P
Oral Presentations
46 12th Australasian Organometallics Meeting
Synthesis of difluorogold(III) complexes supported by
N-ligands
Mohammad Al Bayer, Jason L. Dutton(s)*
Department of Chemistry and Physics, La Trobe University
Well defined organometallic or coordination compounds of Au(III)-fluorides are
exceedingly rare.[1,2] Synthesis of difluorogold(III) complexes supported by N-ligands
(pyridine, 4-DMAP and N-methylimidazole) can be achieved by either reacting XeF2
with Au(I) precursors or from tricationic Au(III) precursors by displacement of the N-
ligands using fluoride from economical KF. The new Au(III) complexes were
structurally characterized by single crystal X-ray diffraction, mass spectrometry and
NMR spectroscopy.
References
[1] R. Kumar, A. Linden, C. Nevado, J. Am. Chem. Soc., 2016, 138, 13790.
[2] M. S. Winstron, W. J. Wolf, F. D. Toste, J. Am. Chem. Soc., 2015, 137, 7921.
Oral Presentations
47 12th Australasian Organometallics Meeting
Insights into the s-Block Metalations of Allylic Phosphines
and Phosphine Oxides
Nimrod M. Eren, Emily Border, Victoria L. Blair*
School of Chemistry, Monash University
Functionalised nitrogen-based systems are crucial as pharmaceuticals,[1] many of
which are formed using organoalkali reagents. However, phosphorus analogues have
not been studied to the same degree, making their synthetic potential through
organoalkali reactions a key topic.
Our group has focused on the comparative metalation studies of allylic-phosphine and
–amine substrates with organolithium and organosodium reagents. Through structural
and solution state studies we have revealed structural-reactivity dependence, from
both donor ligand denticity[2] and allylic chain composition. Extending this study to the
pentavalent phosphorus oxidation state, has allowed the structural elucidation of a
range of allylic anionic phosphine oxides to be characterised revealing ‘Wittig type’
intermediates when their reactivity was probed.
Figure 1: Structural diversity in lithiated allylic phosphine oxides
References
[1] E. Vitaku, D. T. Smith, J. T. Njardarson, Journal of Medicinal Chemistry 2014, 57, 10257-10274. [2] V. L. Blair, M. A. Stevens, C. D. Thompson, Chemical Communications 2016, 52, 8111-8114.
Oral Presentations
48 12th Australasian Organometallics Meeting
Anti-Leishmanial Activity of Organometallic Antimony (V) And Gallium (III) Quinolinolato Complexes
Rebekah N Duffin*, Victoria L Blair, Lukasz Kedzierski and Philip C Andrews
School of Chemistry, Monash University, Australia
The prevalence of neglected tropical diseases is on the rise, with the parasitic ailment
leishmaniasis being no exception. Its locality in 90+ tropical/sub-tropical low
socioeconomic countries and increased cases of established drug resistance, makes
the design and characterisation of new potentially low-cost drug candidates a high
priority.1, 2 Previous studies by Andrews et al had focused primarily on aryl complexes
of the group 15 metal antimony,3 due to the similarities with the current front-line
treatment, however recent investigations into the medicinally relevant gallium has
revealed a whole new potential in the world of organometallic medicinals. Gallium has
shown previous applications in radiopharmaceuticals, anti-cancer agents and a
varying degree of bactericides, but little has been explored in the ways of anti-
parasitics.4 Utilising the medicinally5 and fluorescently active class of 8-hydroxy-
halido-quinolinols, 8 gallium complexes and 6 antimony complexes, were successfully
synthesised and characterised (figure 1), eleven of which have been evaluated for
their anti-leishmanial activity.
References
[1] W. H. Organization, Investing to Overcome the Global Impact of Neglected Tropical Diseases: Third WHO Report on Neglected Tropical Diseases 2015, World Health Organization, 2015.
[2] A. Ponte-Sucre, F. Gamarro, J.-C. Dujardin, M. P. Barrett, R. López-Vélez, R. García-Hernández, A. W. Pountain, R. Mwenechanya and B. Papadopoulou, PLoS Negl. Trop. Dis., 2017, 11, e0006052.
[3] R. N. Duffin, V. L. Blair, L. Kedzierski and P. C. Andrews, Dalton Trans., 2018, 47, 971-980.
[4] F. Minandri, C. Bonchi, E. Frangipani, F. Imperi and P. Visca, Future Microbiol., 2014, 9, 379-397.
[5] M. C. Duarte, L. M. dos Reis Lage, D. P. Lage, J. T. Mesquita, B. C. S. Salles, S. N. Lavorato, D. Menezes-Souza, B. M. Roatt, R. J. Alves and C. A. P. Tavares, Vet. Parasitol., 2016, 217, 81-88.
Figure 1. X-ray structures of the complexes [GaMe(C9H4ONCl2)2] and
[Ga(Me2)C9H4ONCl2]
Oral Presentations
49 12th Australasian Organometallics Meeting
Tunable Photoluminescent Properties of a New Class of
Thermally Robust Monocyclometalated Gold(III)
Complexes
Robert Malmberg, Koushik Venkatesan*
Department of Molecular Sciences, Macquarie University, NSW 2109, Australia
Phosphorescent gold(III) complexes and their possible applications in optoelectronic
devices have gained an increased interest.[1] Our group has studied Au(III) based
monocyclometalated complexes bearing diaryl or dialkyne ancillary ligands exhibiting
room temperature emission in solution, solid state and in PMMA thin films.[2] It was
shown that the emission profile can be tuned by employing different
monocyclometalated ligand frameworks to achieve emission colours covering the
visible spectrum. Although there was a strong correlation of the photoluminescent
quantum yields (em) and the triplet excited state lifetimes (0) on the kind of
monocyclometalated ligand as well as the ancillary ligands, the ancillary ligands
utilized thus far were limited to monodentate ligands. In order to improve the excited
state properties of monocyclometalated complexes, a new structural design was
sought, in which the ancillary ligands were replaced with bidentate ligands.
Herein, we present the synthesis and luminescent properties of two classes of
thermally robust monocyclometalated gold(III) complexes with new ancillary bidentate
ligands that have a dramatic influence on the em and 0.[3] These results are expected
to further contribute to strategies for the deployment of Au(III) complexes as emitter
molecules in phosphorescent organic light emitting diodes (PhOLEDs).
[1] V. W.-W. Yam, E. C.-C. Cheng, Chem. Soc. Rev. 2008, 37, 1806-1806; b) G. Cheng, K. T. Chan, W. P. To, C. M. Che, Adv. Mater. 2014, 26, 2540-2546; c) R. Kumar, A. Linden, C. Nevado, Angew. Chem. Int. Ed. 2015, 54, 14287-14290.
[2] T. von Arx, A. Szentkuti, T. N. Zehnder, O. Blacque, K. Venkatesan, J. Mater. Chem. C 2017, 5, 3765-3769; b) J. A. Garg, O. Blacque, T. Fox, K. Venkatesan, Inorg. Chem. 2010, 49, 11463-11472.
[3] R. Malmberg, M. Bachmann, O. Blacque, K. Venkatesan, Chem. Eur. J. 2019, 25, 3627-3636.
Oral Presentations
50 12th Australasian Organometallics Meeting
Reactions of Planar-Chiral 1-P(S)Ph2-2-CH2OH Ferrocenes
Marcus Korb,a* Julia Mahrholdt,b Xianming Liu,b and Heinrich Langb
a School of Molecular Sciences, The University of Western Australia, Perth, Australia
b Inorganic Chemistry, TU Chemnitz, Germany
Ferrocenyl phosphines are prominent planar-chiral ligands in e.g. Pd-catalyzed
reactions. It has been shown that the introduction of weakly coordinating ortho
substituents, such as vinyl groups and ether functionalities, stabilize the catalytically
active species and increase the productivity and activity.[1] However, to use 1-PPh2-2-
OMe-Fc motif (1), obtained via anionic phospho-Fries reactions,[2] in asymmetric
transformations, results in a low ee within biaryl coupling products.[3]
In the search for better enantioselective catalytic performance, derivatives of 1-
P(S)Ph2-CH2OH-Fc (2) have been explored. However, exchange of the OH
functionality occurs under various conditions, with migration of the sulfur atom towards
the α-CH2-group under mild conditions (Figure 1).[4] The application of the resulting
compounds as ligands within Suzuki-Miyaura reactions for sterically hindered biaryls
is presented, where an ee of up to 69 % could be obtained.
Figure 1. Reaction behaviour of CH2-enlarged P,O-ferrocene (Sp)-2. (a) Based on the formation of triple-
ortho-substituted biaryls within a Pd-catalyzed Suzuki-Miyaura C,C cross-coupling reaction.)
References
[1] D. Schaarschmidt, H. Lang, ACS Catal. 2011, 1, 411–416. [2] M. Korb, D. Schaarschmidt, H. Lang,
Organometallics 2014, 33, 2099–2108; M. Korb, H. Lang, Organometallics 2014, 33, 6643–6659. [3]
M. Korb, H. Lang, Chem. Soc. Rev. 2019, DOI: 10.1039/c8cs00830b. [4] M. Korb, J. Mahrholdt, X. Liu,
H. Lang, Eur. J. Inorg. Chem. 2019, 973–987
Oral Presentations
51 12th Australasian Organometallics Meeting
Metal Complexes for Molecular Electronics: Explorations
of Thioether Anchor Groups
M. Naher,a D. Costa Milan,b I. Planje,b S.J. Higgins,b R.J. Nichols,b P. J. Lowa,*
a School of Molecular Sciences, University of Western Australia
b Department of Chemistry, University of Liverpool
The design and preparation of efficient ‘molecular wires’ that allow the study of charge
transport through electrode|molecule|electrode junctions is of primary interest for the
development of novel molecular electronics and molecular electronic materials.
However, to measure, and ultimately control, electron transport through a molecular
junction one must not only synthesize molecules with desired functions embedded in
the backbone, but also design proper molecule-electrode contacts.
Here we describe the syntheses and electronic properties of a novel series of organic
and organometallic compounds bearing thiomethyl and 3,3-dimethyl-2,3-
dihydrobenzo[b]thiophene (DMBT) functionalities as two different anchor group. The
effects that arise from variation of conjugated backbone structure, the thioether
contacting groups and the metal ancillary ligands (L) on the electronic structure,
spectroscopic properties, chemical reactivity, and behaviour in metal|molecule|metal
junctions will be discussed. In particular, the performance of the thiomethyl and DMBT
functional groups as surface binding moieties, as evaluated within scanning tunneling
microscope break-junction (STM-BJ) and STM based current distance (STM-I(s))
molecular junctions will be presented.
Oral Presentations
52 12th Australasian Organometallics Meeting
Ligand Exchange Reaction and Catalysis of the Conversion of Cyanide and Thiosulfate to Thiocyanate and
Sulfite by a Molybdenum Complex
Sigridur G. Suman1*, Johanna M. Gretarsdottir1
1Science Institute, University of Iceland, Dunhagi 3, 107 Reykjavik, Iceland.
Enzyme catalyzed conversion of cyanide and thiosulfate to thiocyanate and sulfite is well documented [1]. The reaction is metal-free employing rhodanase enzyme. Formation of thiocyanate in the spontaneous reaction of cyanide and sulfur is slow [2]. A few examples are known of cyanide forming thiocyanate when reacting with sulfur bound to molybdenum enzymes [3]. Fewer still examples are known of cyanide forming thiocyanate in a reaction of molybdenum complexes with cyanide [4]. Cyanide easily displaces the DMF ligands of the Mo2O2S4(DMF)3 complex as well as reacts with the disulfide ligand on the complex in a sulfur abstraction reaction [5]. One to three DMF ligands are displaced by cyanide in the exchange reaction to potentially form several different products. The products from the exchange reaction were analyzed to determine the preferred product as (a) the products from the exchange reaction or (b) the products from a sulfur abstraction reaction.
The reactivity of the sulfur abstraction reaction by cyanide with the disulfide to form thiocyanate was studied stoichiometrically as a function of pH. High conversion of cyanide to thiocyanate was achieved in a time period of 20 minutes. Reaction mechanism of the catalytic reaction was investigated experimentally and with DFT calculations.
Catalytic cycle is proposed where initial step requires a sulfur abstraction reaction. Potential deactivation routes of the catalytic cycle were discovered when a catalytically inactive complex was isolated and characterized.
Financial support by the Icelandic Centre of Research grant nr 140945 is gratefully acknowledged.
References
[1] K. R. Leininger, J. W., The Mechanism of the Rhodanese-catalyzed Thiosulfate Cyanide Reaction. J. Biol. Chem. 1967, 243 (April 25), pp. 1892-1899.
[2] David R. Singleton, D. W. S., Improved Assay for Rhodanese in Thiobacillus spp. Appl. Environ. Microbiol., Nov. 1988, pp. 2866--2867.
[3] R. Hille, Molybdenum-containing hydroxylases. Arch Biochem Biophys 2005, 433 (1), pp. 107-116. [4] R. S. Pilato, E. I. Stiefel, Inorganic Catalysis, 2nd ed.; Reedijk, J., Bouwman, E., Eds.; Marcel
Dekker: New York, 1999; pp. 81-152. [5] J. H. Enemark, C. G. Young, Bioinorganic Chemistry of Pterin Containing Molybdenum and
Tungsten Enzymes, Adv. Inorg. Chem. 1993, 40, pp. 1-88. [6] C. G. Young, Models for the molybdenum hydroxylases J. Biol. Inorg. Chem. 1997, 2, pp. 810-816. [7] P. D. Smith, D. A. Slizys, G. N. George, C. G. Young, Toward a Total Model for the Molybdenum
Hydroxylases: Synthesis, Redox, and Biomimetic Chemistry of Oxo-thio-Mo(VI) and -Mo(V) Complexes. J. Am. Chem. Soc. 2000, 122, pp. 2946-2947.
[8] J. M. Gretarsdottir, “Syntheses of new molybdenum-sulfur complexes: Catalytic transformation of cyanide to thiocyanate and in vitro biological studies“, PhD Thesis, University of Iceland, 2018.
Oral Presentations
53 12th Australasian Organometallics Meeting
Rhodium (I)-Vinyl Complexes as Effective Initiators in the
Stereospecific Polymerization of Phenylacetylene
Nicholas Tan 1*, Mark I. Ogden1, Massimiliano Massi1, Andrew B. Lowe1
1Curtin Institute for Functional Molecules and Interfaces (CIFMI), School of Molecular
Life Sciences, Curtin University, Perth, Australia
Rh(I) complexes are well known to mediate polymerization of arylacetylenes such as
phenylacetylene as a route to functional materials. The importance of such materials
are largely due to their optoelectronic properties stemming from the π-conjugated
backbone, and by modification of the side chains useful structural features can be
introduced such as helical conformations which can be applied in stimuli-responsive
materials, gas permeable membrane, molecular recognition, and catalytic studies.
Rh(I)-based complexes are used widely, owing to their low intrinsic oxophilicity,
excellent functional group compatibility and high reactivity towards alkynes. Also,
Rh(I)-based complexes can be effective initiators for the controlled stereospecific
polymerization of substituted arylacetylenes. In this presentation, I present three new
Rh(I)-α-phenylvinylfluorenyl complexes bearing fluorine-functionalised phosphine
ligands, Rh(nbd)(CPh=CFlu)P(4‐FC6H4)3, Rh(nbd)(CPh=CFlu)P(4‐CF3C6H4)3, and
Rh(nbd)(CPh=CFlu)P[3,5‐(CF3)2C6H3]3 (nbd: 2,5‐norbornadiene; Flu: fluorenyl) that
have been evaluated in the stereospecific polymerization of phenylacetylenes[1], with
initiation efficiencies of up to 56 %, yielding low dispersity (Ð = Mw/Mn)
polyphenylacetylenes with high cis-transoidal stereoregularity. In addition, the
controlled-like nature of the polymerization of PA have been demonstrated through the
preparation of block copolymers via sequential monomer addition.
References
[1] Tan, N. S. L. et al. Rhodium(I)-α-Phenylvinylfluorenyl Complexes: Synthesis, Characterization, and Evaluation as Initiators in the Stereospecific Polymerization of Phenylacetylene. Eur. J. Inorg. Chem. 2019, 592–601 (2019).
Oral Presentations
54 12th Australasian Organometallics Meeting
An unprecedented diversity of 1,3-disubstituted ferrocenes
through the halogen ‘dance’ reaction
W. Erb, M. Tazi, K. Al-Mekhlafi, Y. S. Halauko, O. A. Ivashkevich, V. E. Matulis, T.
Roisnel, V. Dorcet, F. Mongin
Institut des Sciences Chimiques de Rennes, Université de Rennes 1
Since its discovery by Miller and Pauson and structure elucidation by Woodward,
Wilkinson and Fisher, ferrocene has always drawn the attention of the chemists
community.1 Therefore, due to its specific properties, it is currently hard to find an area
of chemistry free of ferrocene derivatives.
However, the field remains dominated by monosubstituted, 1,1’- and 1,2-disubstituted
derivatives which can be easily prepared by using aromatic electrophilic substitution
or deprotometallation followed by electrophilic trapping. In sharp contrast, the
chemistry of 1,3-disusbtituted ferrocenes remains by far less explored although
promising applications are reported due to the large angle between the two
substitutents.2 This results from the lack of easy and general syntheses of these
derivatives.
Here, we will show how the halogen ‘dance’ reaction, a stability driven reaction, can
be used as a key step to access 1,3-disubstituted ferrocene derivatives.3 An efficient
control of the reaction outcome can be reached through the careful choice of directing
and protective group (DG and PG, respectively) and pave the way toward highly
functionalized ferrocene compounds.
References
[1] (a) T. J. Kealy, P. L. Pauson, Nature 1951, 168, 1039; (b) S. A. Miller, J. A. Tebboth, J. F. Tremaine, J. Chem. Soc. 1952, 632; (c) Ferrocenes: Ligands, Materials and Biomolecules; Eds. P. Stepnicka; Wiley: Hoboken, NJ, 2008.
[2] (a) T. Muraoka, K. Kinbara, T. Aida, Nature 2006, 440, 512; (b) J. Y. C. Lim, P. D. Beer, Eur. J.
Inorg. Chem. 2017, 2017, 220.
[3] (a) M. Tazi, W. Erb, Y. S. Halauko, O. A. Ivashkevich, V. E. Matulis, T. Roisnel, V. Dorcet, F.
Mongin, Organometallics, 2017, 36, 4770; (b) M. Tazi, M. Hedidi, W. Erb, Y. S. Halauko, O. A.
Ivashkevich, V. E. Matulis, T. Roisnel, V. Dorcet, G. Bentabed-Ababsa, F. Mongin,
Organometallics, 2018, 37, 2207.
Oral Presentations
55 12th Australasian Organometallics Meeting
Direct reaction—a simple route to synthesis
organoioamidodidolanthanoid(II/III) complexes
Zhifang Guo, Victoria Blair, Glen B. Deacon*, Peter C. Junk*
School of Chemistry, Monash University, Clayton 3800, Australia.
College of Science & Engineering, James Cook University, Townsville 4811, Qld,
Australia.
Heteroleptic lanthanoid(II/III) metal-organic compounds, including hydrides, amides,
alkoxides, aryloxides, cyclopentadienyls have been synthesized from sources of
LnLX2, LnL2X, LnLX (X = halide). [1] Suitable rare earth reactants [Ln(L)nX3-n] (X = Cl,
Br, I) have been widely prepared by metathesis reactions. However, metathesis
syntheses of [Ln(L)nX3-n] (or [LnLX]) have potential rearrangement outcomes. This
report describes a simple method—direct reaction (an effective, metal-based route) to
obtain a number of lanthanoid complexes [Ln(L)nI3-n] with high yields, from excess of
metals with iodine and ligand in thf.
[Ln(DFForm)2I(thf)2] [Ln(DFForm)I2(thf)3] [Ln(DippForm)I2(thf)3] [Ln(Me2pz)I2(thf)3] [Ln(Me2pz)I2(thf)4]
References
[1]. (a) R. Duchateau, C. T. van Wee, A. Meetsma, J. H. Teuben, J. Am. Chem. Soc., 1993, 115,
4931-4932; (b) J. W. Evans, R. A. Keyer, J. W. Ziller, Organometallics, 1993, 12, 2618-2633;
(c) P. B. Hitchcock, S. A. Holmes, M. F. Lappert, S. Tian, Chem. Commun., 1994, 2691-2692;
(d) W. J. Evans, R. N. R. Broomhall-Dillard, J. W. Ziller, Organometallics, 1996, 15, 1351; J.
Organomet. Chem., 1998, 569, 89-97; (e) A. A. Trifonov, E. N. Kirillov, A. Fischer, F. T.
Edelmann, M. N. Bochkarev, Chem. Commun., 1999, 2203-2204; (f) H. Schumann, J. A.
Meese-Marktscheffel, L. Esser, Chem. Rev., 1995, 95, 865-986.
LnX3 + n ML Ln(L)nX3-n + n MX (1)
X = halide, Cl, Br, IM = alkali metal, Li, Na, K
2 X2LnL LnL2X + LnX3
1/2 LnL3 + 1/2 X2LnL
(2)
3 LnLnX3-nn LnL3 + (3-n) LnX3 (3)
Poster Presentations
56 12th Australasian Organometallics Meeting
A Mechanistic Study of Ruthenium (II) Catalysed C-H
Amidation and Thioamidition
W. A. O. Altalhi, A. I. McKay, P. S. Donnelly, A. J. Canty, R. A. J. O’Hair*
School of Chemistry, The University of Melbourne
Amides and thioamides are important functional groups which are widely utilised in the
chemical and pharmaceutical industries. Traditional methods for their syntheses suffer
from poor atom economy (stoichiometric amounts of waste) and tedious
prefunctionalisation.[1] New efficient methods for amide synthesis involving the
insertion of an isocyanate into a C-H bond have been recently reported.[2]
Unfortunately, most of studies can be classified as “black box” since they typically
feature complicated cocktails of additives and solvents and their underlying
importance with regards the proposed catalytic cycle is rarely explained.
In this study, we use a combination of gas-phase and solution experiments together
with DFT calculations to investigate the mechanism of Ruthenium (II) catalysed C-H
amidation of N,N’-dimethylbenzylamine. This substrate presents an attractive target
as amide synthesis has already been reported by ortholithiation, phenyl isocyanate
insertion, followed by hydrolysis.[3] We isolate and crystallographically characterise a
key C-H activated intermediate and study its reactivity with a range of alkyl- and aryl
isocyanates both in solution and the gas phase using ESI-MS. Other key steps of the
mechanism have also been examined, as well as attempts to develop C-H
thioamidation protocols.
References
[1] Bode, J.W., et. al. Nature, 2011, 480, 471-479.
[2] Cheng, C.-H.; et. al., Org. Lett., 2012, 14, 4262-4265.
[3] Hauser, C.R.; et. al., J. Org. Chem., 1963, 28, 3461-3465.
C
N
N
H
O H
Poster Presentations
57 12th Australasian Organometallics Meeting
Charting the Reaction Coordinate in ‘Beryllocene’
Stephen P Best,1* Albert Paparo,2 Courtney Ennis,3
1 School of Chemistry, The University of Melbourne, 2 School of Chemistry Monash
University, 3 School of Chemistry, Otago University.
We aim to establish the framework for the interpretation of the vibrational spectra of
dynamic molecules. This contribution focuses on ‘beryllocene’, 5, 1-Be(C5H5)2 – Bc,
a dynamic molecule with activation energies below ca. 8 kJ mol-1 [1]. Molecular
mechanics and theory are broadly in line with these conclusions [2] and a measure of
the dynamic behaviour of the molecule at RT is evident from comparison of the 298
and 173 K X-ray structures shown below. In addition to the large increase in the
thermal ellipsoids, the centroid positions are drawn indicating a 2, 5 geometry. This
is the computed transition state for rotation of the 1-bound ring.
We have recently shown that the temperature dependence of the IR spectra can be
used to chart the reaction coordinate for interconversion between rotamers of
ferrocene (Fc) and that medium-dependent differences in the activation energy lead
to differences in the band profile for Fc in its different states [3]. In this contribution we
outline our recent studies into the extension of the dynamic vibrational spectroscopic
approach to Bc. Comparatively simple measures of the temperature dependence of
the vibrational spectra have the potential to provide direct experimental measures of
the reaction coordinate and barrier for dynamic molecules and with it to provide
important insights into reaction dynamics more generally.
X-ray structures of Bc at 173 K (left) and 298 K (right) [1c]. Thermal elipsoids are drawn at the 50%
probability level.
References
[1] a. K. W. Nugent, J. K. Beattie, J. Chem. Soc., Chem. Commun. 1986, 186-187; b. K. W. Nugent, J. K. Beattie, L. D. Field, J. Phys. Chem. 1989, 93, 5371-5377; c. I. Hung, C. L. B. Macdonald, R. W. Schurko, Chem. - Eur. J. 2004, 10, 5923-5935.
[2] P. Margl, K. Schwarz, P. E. Bloechl, J. Am. Chem. Soc. 1994, 116, 11177-11178. [3] S. P. Best, F. Wang, M. T. Islam, S. Islam, D. Appadoo, R. M. Trevorah, C. T. Chantler, Chem.
Eur. J. 2016, 22, 18019-18026.
Poster Presentations
58 12th Australasian Organometallics Meeting
Alkynyltellurolate Ligands and a Solvatochromic
Rhenium(I) Complex
Liam K. Burt, Anthony F. Hill*
ANU Research School of Chemistry, Australian National University
Sullivans Creek Road, Acton, ACT, 2601
Organotellurium metal complexes remain scarce in the literature despite growth in
recent years. These tellurium-based ligands are classified as telluroethers (R–Te–R),
tellurolates (RTe– + M’) or tellurides (Te2–) depending on the binding mode to the metal
centre. Rare complexes featuring tellurolate ligands have been flagged as highly
unstable due to air sensitivity, diffusive sets of orbitals and further reactivity.
This work presents the first examples of alkynyltellurolate complexes as a continuation
of the alkynylselenolate species previously explored.[1] Iron and rhenium-based
species [CpFe(TeCCPh)(CO)(PPh3)] and [(bpy)Re(TeCCSiMe3)(CO)3] were
synthesised via lithiation of an alkyne, chalcogen insertion and subsequent
metathesis.
Further investigation of this alkynyltellurolate rhenium complex revealed interesting
photophysical properties, including visible solvatochromism.
Molecular structure obtained for [(bpy)Re(TeCCSiMe3)(CO)3].
References
[1] Caldwell, L. M., Hill, A. F., Hulkes, A. G., McQueen, C. M. A., White, A. J. P., Williams, D. J.,
Organometallics 2010, 29, 6350.
Poster Presentations
59 12th Australasian Organometallics Meeting
Single-Molecule Magnets: Lanthanide - β Diketonates
“Triangles”
Chiara Caporale,a Alexandre N. Sobolev,b Wasinee Phonsri,b Keith S. Murray,b
Massimiliano Massi,a and Rebecca O. Fuller a*
a School of Molecular and Life Science, Curtin University, Bentley, WA
b School of Chemistry, Monash University, Clayton, VIC
c School of Molecular Sciences, The University of Western Australia, Crawley, WA
Single-molecule magnets (SMMs) are being developed as potential components for
information storage.[1] Since the discovery of a dodecanuclear MnIII/MnII acetate
complex,[2] researchers have continued to explore molecules that retain magnetisation
even after the applied field is removed. A large number of different SMMs are being
developed, including those based on homometallic 3d or 4f clusters and heterometallic
3d-4f complexes. Trigonal lanthanide complexes are known to display interesting
magnetic properties.[3] The symmetry and magnetic moment is known to play role in
the observed properties. Our research has focus its attention in the synthesis and
characterisation of lanthanide trinuclear clusters, in order to provide a detailed
knowledge of the structure-properties relationship of these materials and aim to
facilitate the future development of high performance SMMs for the next generation of
devices.
Figure 1: Example of Lanthanide - β Diketonates “triangle”
References
[1] Feltham, H. L. C.; Brooker, S., Coord. Chem. Rev, 2014, 276, 1.
[2] Sessoli, R; Tsai, H. L.; Schake, A. R. et al., J. Am. Chem. Soc., 1993, 115, 1804.
[3] L. F. Chibotaru, L. Ungur, A. Soncini, Angew. Chem. Int. Ed. 2008, 120, 4194-4197
Poster Presentations
60 12th Australasian Organometallics Meeting
Use of Ag(C6F5) or Bi(C6F5)3 instead of HgAr2 reagents in
redox transmetallation/protolysis reactions of free
lanthanoid metals
Glen B. Deacon, Zhifang Guo, Jenny Luu, Victoria Blair, Peter C. Junk
School of Chemistry, Monash University, Clayton 3800, Australia.
College of Science & Engineering, James Cook University, Townsville 4811, Qld,
Australia.
We have established redox transmetallation/protolysis (RTP) reactions of lanthanoid
metals with diarylmercurials and protic agents (phenols, amines, pyrazoles,
formamidines, and cyclopentadienes) to be an effective synthesis of highly reactive
rare earth compounds. [1]
The method is competitive with metathesis, but the synthesis would be more attractive
if a less toxic metal could be employed. We have now examined both AgC6F5 and
Bi(C6F5)3 as alternative reagents. [2, 3]
A new synthesis of AgC6F5 from commercially available, air-stable reagents helps. [2]
Both AgC6F5 and Bi(C6F5)3 have been tested in the synthesis of lanthanoid pyrazolates
for a wide range of Ln metals and several pyrazoles. [2, 3] Both reagents are effective
but have limitations. [4]
References
[1]. (a) G. B. Deacon, C. M. Forsyth, S. Nickel, J. Organomet. Chem., 2002, 647, 50- 60; (b) G. B.
Deacon, Md E. Hossain, P. C. Junk, M. Salehisaki, Coord. Chem. Rev., 2017, 340, 247-265.
[2]. Z. Guo, J. Luu, V. Blair, G. B. Deacon, P. C. Junk. Eur. J. Inorg. Chem., 2019, 1018-1029.
[3]. Z. Guo, V. Blair, G. B. Deacon, P. C. Junk. Chem. Eur. J., 2018, 24, 1-12
[4]. Support of the Australian Research Council and the Australian Synchrotron are gratefully
acknowledged.
Ln + n/2 HgAr2 + n LH Ln(L)n + n/2 Hg + n ArH (1)
n = 2, 3 Ar = C6F5, Ph, CCPh
Ln + 3 AgC6F5 + 3 LH Ln(L)3 + 3 Ag + 3 C6F5H (2)
Ln + Bi(C6F5)3 + 3 LH Ln(L)3 + Bi + 3 C6F5H (3)
Ag2O + 2 C6F5H [Ag2(C6F5)2(py)3] + H2O (4)py
Poster Presentations
61 12th Australasian Organometallics Meeting
Lewis acids: Versatile catalysts for fundamental
transformations and polymerisations
Deepamali Dissanayake, Siyuan Zhai, Zhizhou Liu, Alysia Draper, William McAllister,
Dragoslav (Drasko) Vidovic*
School of Chemistry, Monash University
Recent evidence has suggested that Lewis acid catalysis is underdeveloped due to
inadvertent presence of hidden Bronsted acids. In recent years we have developed
several NacNac-supported aluminium complexes that showed exceptional activity as
Lewis acid catalysts for various Diels-Alder cycloadditions, Michael additions and
borylations.[1] It was also discovered that a very subtle structural modification led to
unprecedented polymerisation of cyclic dienophiles. Lastly, our progress towards
chiral system will also be discussed.
References
[1] a) J. Org. Chem. 2018, 83, 529. b) Dalton Trans. 2017, 46, 753. c) Chem. Eur. J. 2015, 21, 11344.
Poster Presentations
62 12th Australasian Organometallics Meeting
Optical Nonlinearities of Y-shaped and H-shaped
Arylalkynylruthenium Complexes
Jun Du, Mahbod Morshedi, Mahesh S. Kodikara, Marek Samoc, Marie P. Cifuentes,
Mark G. Humphrey*
Research School of Chemistry, Australian National University
Straightforward syntheses of bis[bis{1,2-bis(diphenylphosphino)ethane}ruthenium]-
functionalized1,3,5-triethynylbenzene-cored complexes via a methodology employing
“steric control” permit facile formation of Y-shaped Sonogashira coupling products and
distorted-H-shaped homo-coupled quadrupolar products. The quadratic and cubic
optical nonlinearities were assessed by the hyper-Rayleigh scattering and Z-scan
techniques. The cyclic voltametric data reveal two reversible metal alkyntl-localized
oxidation process for all complexes. Computational studies based on time-dependent
density functional theory were applied to assign the key low-energy transitions in the
linear optical spectra and to compute the quadratic nonlinear optical tensorial
components.
Poster Presentations
63 12th Australasian Organometallics Meeting
A [3]Rotaxane With Coupled Rotary and Linear Shuttling
Motion
James A. Findlay, James D. Crowley*
Department of Chemistry, University of Otago
Control over molecular motion will have important repercussions throughout
nanotechnology, and this was recognized by the awarding of the 2016 Nobel Prize in
Chemistry “for the design and synthesis of molecular machines”. Research groups,
including Prof. J-P Sauvage’s, have reported switchable catenane and rotaxane-
based molecular machines, taking advantage of the change in coordination preference
of copper ions between the 1+ (usually tetrahedral) and 2+ (5 or 6 coordinate)
oxidation states to alter the position of a macrocycle within mechanically interlocked
architectures (MIAs).1,2 Previously, our lab has reported molecular switches using the
same stimulus to produce rotary motion within non-interlocked ferrocene (Fc)-based
systems.3 The synthesis of a [3]rotaxane is described where a bipyridine (bipy)-
containing macrocycle is mechanically interlocked to each ‘arm’ of a 1,1’-disubstituted
Fc ligand. The two thread ‘arms’ provide both a bidentate and a tridentate coordination
site for binding of Cu(I) and Cu(II) ions with the bipy-macrocycle, respectively. This
design would give rise to redox controlled linear shuttling of the macrocycle along the
thread, simultaneously switching the bidentate chelates of the threads between a π-π
stacked state and being occupied by the sterically demanding macrocycle, causing
rotation about the Fc joint (Figure 1). To the best of our knowledge this would be the
first example of coupled molecular rotary and linear shuttling motions.
References
[1] Durot, S., Reviriego, F., Sauvage, J-P., Dalton Trans., 2010, 39, 10557-10570. [2] Champin, B., Mobian, P., Sauvage, J-P., Chem. Soc. Rev., 2007, 36, 358-366. [3] Scottwell, S. Ø., Elliott, A. B. S., Shaffer, K. J., Nafady, A., McAdam, C. J., Gordon, K. C., Crowley, J. D., Chem. Commun. 2015, 51, 8161. [4] Lewis, J. E. M., Bordoli, R. J., Denis, M., Fletcher, C. J., Galli, M., Neal, E. A., Rochettea, E. M. and Goldup, S. M. Chem. Sci. 2016, 7, 3154.
Poster Presentations
64 12th Australasian Organometallics Meeting
Bimetallic Group 14 Complexes Stabilised by Bis(N,N’-
diarylamidinate) Ligand
Palak Garg, Cameron Jones*
School of Chemistry, Monash University
The last two decades have seen a search for main-group metal complexes as cheaper
and less toxic alternatives to the transition metal complexes in several applications,
e.g. catalysis.1 The tunable steric and electronic properties of amidinate ligands
[RC{NR’}2]- gives kinetic stability to low valent main-group metal complexes. Recently,
bifunctional amidinate ligands have successfully allowed access to unusual rare earth
and group 13 metal complexes.2 Herein, we report the synthesis of group 14 bimetallic
complexes XML-C6H4-LMX (Scheme 1) using salt metathesis reactions. Currently, we
are investigating the possibility of forming bimetallic group 14 hydride complexes. The
bimetallic hydride complexes are expected to possess unique bifunctional catalytic
properties as a result of synergistic effects between adjacent metal centres. The
reduction of these bimetallic complexes may possibly lead to the main group metal
coordinating polymers.
Scheme 1. Synthetic of bimetallic group 14 complexes.
References
[1] Cotton, F. A.; Wilkinson, G.; Murillo, C. A.; Bochmann, M. Advanced Inorganic Chemistry, 6th Ed.
1999, Wiley, Chichester, United Kingdom.
[2] (a) Li, M.; Hong, J.; Chen, Z.; Zhou, X.; Zhang, L. Dalton trans. 2013, 42, 8288.
(b) Lei, Y.; Chen, F.; Luo, Y.; Xu, P.; Wang, Y.; Zhang, Y. Inorganica Chim. Acta 2011, 368, 179.
HN
N NH
N
R
R
R
R
1. nBuLi, THF
2. MX2, RT N
N N
N
R
R
R
R
MM
X
X
R =
M = Ge, Sn
X = Cl
Poster Presentations
65 12th Australasian Organometallics Meeting
Antitumor dinuclear platinum (II) complexes with DNA
imbedding groups
Chuanzhu Gaoa*,b*, Tianshuai Wanga, Yan Zhanga, Zhuxin Zhanga, Glen B. Deaconb
aFaculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
bSchool of Chemistry, Monash University, Clayton 3800, Australia.
Aromatic groups could embed in grooves of the double helix structure of tumor DNA and act as antitumor drugs such as Mitoxantrone. Some of them have been introduced and linked two trans-1R-2R-cyclohexanediamines(DACH) as bridges, and novel dinuclear platinum complexes have been synthesized and characterized. We hope that the new binuclear platinum complexes can not only overcome cross-
resistance due to their different mononuclear structures from cisplatin, but also play a
synergistic anti-tumor role due to the introduction of DNA embedding groups.
In vitro cytotoxicities of dinuclear platinum complexes against tumor cells were
evaluated using MTT assay. Results indicated that lipid-water partition coefficient has
important influences on the antitumor activity and some of them showed better activity
than oxaliplatin and carboplatin.
References
[1]. C. Yu, C. Gao*, L. Bai, Bioorg. & Med. Chem. Lett., 2017, 27, 963-966.
[2]. Z. Zhang, C. Li, C. Gao*, Inorg. Chim. Acta., 2017, 45,166-172.
[3]. C. Gao*, T. Wang, Y. Zhang, Appl. Organomet. Chem., 2015, 29, 38-142.
[4]. Support of the s National Natural Science Foundation and Doctoral Program of the Ministry of Education of PR China are gratefully acknowledged.
Poster Presentations
66 12th Australasian Organometallics Meeting
Synthesis and Reactivity of Carbon-Rich and
Cumulenylidene Ligands in Iron and Ruthenium
Complexes
Michael R. Hall, a Rachel R. Steen,a,b Paul J. Low,a and Jason M. Lynamb
a School of Molecular Sciences, University of Western Australia, Perth, Australia
b Department of Chemistry, University of York, York, UK
Carbon-rich ligands currently attract interest for their unusual electronic structures,
having application as components in electronic and optoelectronic devices.[1]
Recently, attention has turned to their use in organic synthesis, with novel aryl-spaced
cumulene ligands being identified as potential reagents for regioselective alkyne
activation.[2] A series of trapping reactions of metallacumulenes containing phenyl and
thienyl spacing units are reported, both from vinylidene and alkynyl precursors.
Figure 1. Dynamic vinylidene – acetylide – cumulene equilibrium
References
[1] Marqués-González, S., & Low, P. J. Aust. J. Chem., 2016, 69(3), 244-253; Garner, M. H., Bro-Jorgensen, W., Pedersen, P. D. & Solomon, G. C. J. Phys. Chem. C., 2018, 122(47), 26777-26789
[2] Eaves, S. G., Hart, S. J., Whitwood, A. C., Yufit, D. S., Low, P. J. & Lynam, J. M. Chem. Commun.,
2015, 51(45), 9362-9365
Poster Presentations
67 12th Australasian Organometallics Meeting
Simple Metalation of Terminal Acetylenes: Synthesis of
High Purity Metal Acetylide Half- Sandwich Complexes
Daniel P. Harrison, Paul J. Low*
School of Molecular Science, University of Western Australia
Metal acetylide half-sandwich complexes are used as model complexes for
explorations of through molecule electron-transfer processes. Studies of mixed
valence systems using spectro-electrochemistry improves knowledge of electron-
transfer processes towards molecular electronic applications. Here we report a
revised, “one pot”, synthesis that affords these complexes in high-yield and excellent
purity, with minimal purification and workup required.
Examples of the electrochemical response of these compounds will be presented, and
the subtle differences in electronic structure evinced by UV-vis-NIR and IR
spectroelectrochemical studies will be discussed.
Poster Presentations
68 12th Australasian Organometallics Meeting
Bismuth(III) phosphinate 1D-coordination polymers as
antibacterial additives
Megan Herdman, Melissa Werrett, Rajini Brammananth, Warren Batchelor, Phil
Andrews*
School of Chemistry, Monash University
Antimicrobial resistance has been recognized by the World Health Organization as a
global threat requiring urgent action.[1] The major concern of multi-resistant bacteria is
the high prevalence in hospitals and other healthcare environments. A method to
reduce the growth of bacteria on surfaces is to introduce antimicrobial functionality into
a range of surfaces within hospitals and healthcare facilities.
Bismuth has been used medicinally due to its reported antimicrobial activity and low
toxicity.[2-4] We have previously shown bismuth(III) phosphinate complexes BiPhL2
display antibacterial activity while BiL3 complexes do not inhibit bacterial growth.[5] We
have therefore synthesised a series of bismuth(III) phosphinate complexes of the type
BiPh2L to further explore the structure activity relationship. The complexes (BiPh2L)
form 1D coordination polymers (Figure 1) and thus are relatively insoluble in common
solvents, making them ideal candidates to incorporate into materials.
Antibacterial testing was conducted on the solid complexes, with the results showing
antibacterial activity towards both Gram positive and Gram negative bacteria.
Incorporation within a cellulosic polymer matrix produced Bi-containing paper, which
also showed antibacterial activity at low complex loadings. Studies into the leaching
of the complex from the composites have shown that Bi can be detected in the water,
suggesting the complex leaches out and gives rise to the zones of inhibition in
antibacterial testing.
Figure 1 – Crystal structure showing 1D-coordination polymer of the complex [BiPh2(OOP(CH3)2)].
References
[1] World Health Organization, 2014, 1-232.
[2] M.T. Busse, Iman, P. Junk. R. Ferrero, P. Andrews, Chem. Eur. J. 2013, 19, 5264-5275.
[3] A. Pathak, V. Blair, R. Ferrero, M. Mehring, P. Andrews, Chem. Commun. 2014, 50, 15232-15234.
[4] T. Kotani, D. Nagai, K. Asahi, H. Suzuki, F. Yamao, N. Kataoka, T. Yagura, Antimicrob Agents
Chemother. 2005, 50, 2729-2734.
[5] M. Werrett, M. Herdman, R. Brammananth, U. Garusinghe, W. Batchelor, P. Crellin, R. Coppel, P. Andrews.
Chem. Eur. J. 2018, 24, 12938-12949.
Poster Presentations
69 12th Australasian Organometallics Meeting
Applications of Gold Cocatalysis & New Phosphine
Ligands for Palladium-Catalysed Cross-Couplings
Curtis C. Ho*
*School of Natural Sciences – Chemistry, University of Tasmania
We have demonstrated a novel method employing gold(I) cocatalysis for enhancing
the efficiency of fundamental cross-coupling reactions catalysed by
palladium/phosphine complexes. Our results are consistent with cationic gold(I)
species serving primarily as phosphine scavengers generating putative
monophosphine-ligated Pd(0) active catalyst species in situ, as recently predicted by
density functional theory.[1] We will also present our progress towards developing new
classes of phosphine ligands for the generation of stable monophosphine-ligated
Pd(0) catalysts.
Figure 1. Cationic gold(I) species serving as a phosphine scavenger enhancing reactivity in cross-
couplings.
References
[1] Y. Khaledifard, B. Nsiri, S. A. Javidy, A. V. Sereshk, B. F. Yates, A. Ariafard, Organometallics 2017, 36,
2014.
Poster Presentations
70 12th Australasian Organometallics Meeting
Confirmation of Redox Transmetallation/Protolysis
Reaction Between HgC6F5, lanthanoid metals and protic
agents
Ryan Huo, Yu Qing Tan, Zhifang Guo, Victoria Blair, Glen B. Deacon*
School of chemistry, Monash University, Clayton 3800, Australia.
Previous studies have proposed that the redox transmetallation/protolysis (RTP)
synthesis of reactive trivalent lanthanoid organometallics, organicamides, arylamides
etc from free lanthanoid metals, HgAr2 and a protic agents (amine, formamidine,
pyrazole, phenol etc) proceeds by the following steps.1-4
To confirm this hypothesis, Hg(C6F5)2 was reacted with protic agents under one week
of sonication in dry THF. This resulted in the formation of minimal quantities of C6F5H,
suggesting that protolysis/redox transmetallation reaction (PRT) occurs at a slow rate.
An RTP reaction involving ytterbium metal, Hg(C6F5)2 and a bulky proligand (N,N’-
bis(2,6-diisopropylphenyl)formamidine (DippFormH)) in THF, proceeds to completion
in less than two hours via stirring, these combined results indicate that the RTP
reaction is favourable over protolysis/redox transmetallation PRT.
References 1. M. L. Cole , G. B. Deacon , C. M. Forsyth , P. C. Junk , K. Konstas and J. Wang , Chem. Eur. J., 2007, 13 ,
8092 -8110.
2. G. B. Deacon , G. D. Fallon , C. M. Forsyth , S. C. Harris , P. C. Junk , B. W. Skelton and A. H. White ,
Dalton Trans., 2006, 6, 802-812.
3. G. B. Deacon , C. M. Forsyth and S. Nickel , J. Organomet. Chem., 2002, 647 , 50
4. J. Lefèvre, G. B. Deacon, P. J. Junk and L. Maron, Chem. Commun., 2015, 51, 15173-15175.
Poster Presentations
71 12th Australasian Organometallics Meeting
Synthesis of New, Super Bulky β-Diketiminate Ligands and
their Application in Low-Oxidation State Metal Chemistry
Dafydd D. L. Jones, Cameron Jones*
School of Chemistry, Monash University
β-Diketiminate (or Nacnac) ligands have found great success in coordination
chemistry since 1968.[1] The facile synthesis of these ligands has given immense
scope in tuning the sterics and electronics of these systems.[2] In particular the use of
sterically bulky Nacnac systems with large N-substituents have led to many
breakthroughs in low-oxidation state metal chemistry, with Nacnac systems using 2,6-
diisopropyl (Dipp) aniline being most famous. More sterically demanding Nacnac
systems have proven to be problematic as they either are synthetically difficult to
access or can undergo decomposition reactions due to proximal acidic protons.
Recent reports have shown that replacing the isopropyl groups of the Dipp aniline with
isopentyl groups (DiPeP), has shown promise with the synthesis of reactive group two
hydrides and a low-oxidation magnesium (I) dimer, which is of particular note due to
its large Mg-Mg bond distance compared to its analogues.[3,4] This does still require
several synthetic steps to the DiPeP aniline, and some of these complexes are difficult
to isolate due to their high solubility.
Therefore the synthesis of bulkier, but more synthetically accessible anilines was
herein explored. The aim of which is to synthesise new β-diketiminate ligands, and to
explore the utility of these ligands in low-oxidation state metal chemistry, particularly
that of magnesium and aluminium (Figure 1). The successful synthesis and
stabilisation of magnesium complexes is discussed, as well as comparative reactivity
and steric bulk compared to the established analogues.
Figure 1. A super bulky Nacnac ligand system using 2,4,6-tricyclohexyl aniline, with the synthetic route
to one of the target metal complexes, a magnesium (I) dimer.
References
[1] Parks, J. E, Holm, R. H. Inorg. Chem. 1968, 7, 1408-1416
[2] C. Chen, S. M. Bellows, P. L. Holland, Dalton Trans., 2015, 44, 16654-16670
[3] T. X. Gentner, B. Rösch, G. Ballmann, J. Langer, H. Elsen and S. Harder, Angew. Chem., Int. Ed.,
2019, 58, 607–611.
[4] B. Rösch, T. X. Gentner, H. Elsen, C. A. Fischer, J. Langer, M. Wiesinger, S. Harder, Angew.
Chem., Int. Ed., 2019, 58, 5396–5401.
Poster Presentations
72 12th Australasian Organometallics Meeting
Diferrocenyl Co- and Fe-Carbonyl Clusters
Marcus Korb,a* Sebastian Walz,b Xianming Liu,b Marco Rosenkranz,c Alex Popov,c
and Heinrich Langb
a School of Molecular Sciences, The University of Western Australia, Perth; b Inorganic
Chemistry, TU Chemnitz; c Institute for Solid State Research, Dresden, Germany
The introduction of ferrocenyl fragments as redox active moieties allows for the study
of electronic and Coulombic interactions through the core of various types of
molecules. Iron- and Cobalt-based clusters were intensively been studied in the 1970s
and recently returned to focus with demonstrations of interactions with the iron atom
of an attached ferrocenyl moiety in a monomeric model compound.[1] Although,
replacement of carbonyls by e.g. dppf is a common procedure to attach ferrocenyl
groups to cluster cores, direct functionalization is less readily achieved.
Applying a recently published procedure for the synthesis of pure FcPCl2,[2] we
synthesized novel derivatives of well-known cluster species Fe3(CO)9(μ3-PFc)2 (1) and
Co4(CO)10(μ3-PFc)2 clusters (2) (Figure 1). The electrochemical behaviour was
investigated for the anodic (ferrocenyl-based) and cathodic (core-based) region,
revealing stable one-electron redox products, which were further explored by in situ
NIR and IR spectroelectrochemical measurements. Furthermore, the presence of the
phosphorous atoms allowed for detailed in situ EPR results of 1∙– and confirmed a
core-rearrangement at low potentials.
Figure 1. ORTEP (left, 50 % probability level) and CV and Square Wave diagrams (right) of 1. (Fc* =
Decamethylferrocene.)
References
[1] F. Döttinger, M. R. Ringenberg, Organometallics 2019, 38, 586–592; M. Häßner, J. Fiedler, M. R.
Ringenberg, Inorg. Chem. 2019, 58, 1742–1745. [2] B. A. Surgenor, L. J. Taylor, A. Nordheider, A. M.
Z. Slawin, K. S. Athukorala Arachchige, J. D. Woollins, P. Kilian, RSC Adv. 2016, 6, 5973–5976.
Poster Presentations
73 12th Australasian Organometallics Meeting
Synthesis and Spectroelectrochemical Studies of
Ruthenium Alkynyl Complexes
George A. Laffan,1 Mark G. Humphrey,1 Mahbod Morshedi1
1Research School of Chemistry, Australian National University, Canberra, ACT, 2601
Extended ruthenium alkynyl complexes have been synthesized, and the possibility of
switching their molecular optical properties via electrochemical means has been
investigated. Incorporation of inductive electron-donating or – withdrawing
substituents (NO2 and NPh2 respectively) at the meta-position of the arylalkynyl ligand
bridges, as shown below, modifies the electronic characteristics of the complexes. The
target complexes were designed to permit sequential and reversible oxidation of the
complexes through two oxidation states. Each oxidation step induced a noticeably
unique optical response, creating multistate molecular switches.
Poster Presentations
74 12th Australasian Organometallics Meeting
The odd nature of tungsten C3 and C5 complexes
Richard A. Manzano, Anthony F. Hill
Research School of Chemistry, Building 137, Sullivans Creek Road, The Australian
National University, Canberra, ACT, 2601, Australia.
Transition metal based polyyne chemistry has been an emerging topic within the
organometallics field. In particular, the development of odd-numbered sp-hybridised
carbon chains have seen a recent surge within the literature over the past decade.[1]
A simple, yet elegant method has been developed towards the synthesis of tungsten
propargylidynes [W(CCCR)(CO)2Tp*] (C3)[2] and pentadiynylidyne
[W(CCCCCR)(CO)2Tp*] (C5)[3] complexes via palladium-mediated cross coupling
of the tungsten bromocarbyne [W(CBr)(CO)2Tp*] and various species of terminal
alkynes.
Further reactivity of the trimethylsilylpentadiynylidyne [W(CCCCCSiMe3)(CO)2Tp*]
demonstrates its utility as a C5 scaffold to afford pentacarbido complexes.
Crystal structure of the trimethylsilylpentadiynylidyne complex [W(CCCCCSiMe3)(CO)2Tp*)]
References
[1] Hill, A. F.; Colebatch, A. L.; Cordiner, R. L.; Dewhurst, R. D.; McQueen, C. A. M.; Nguyen, K. T. H.
D.; Shang, R.; Willis, A. C. Comments on Inorganic Chemistry 2010, 31, 121-129.
[2] Hill, A. F.; Manzano, R. A. Dalton Transactions 2019, 48, 6596-6610.
[3] Hill, A. F.; Manzano, R. A. Angewandte Chemie International Edition 2019, 58, 7357-7360.
Poster Presentations
75 12th Australasian Organometallics Meeting
Towards the Assembly Triple Hydrogen Bonded Transition
Metal Complexes
Aidan P. McKay, David A. McMorran*
Department of Chemistry, University of Otago
The understanding of the structural features within molecular compounds that facilitate
their intermolecular assembly by hydrogen bonding, either with themselves or with
complementary species, is important for the construction of functional co-crystallised
systems and the development of rational methods for their synthesis.[1, 2] Here we will
describe a range of transition metal complexes containing known and novel ligands
which contain either the acceptor-donor-acceptor (ADA) or the complementary donor-
acceptor-donor (DAD) motifs, and our recent results in characterising these in the solid
state. Structures of palladium(II) and platinum(II) 2-phenylpyridine, ruthenium(II) bis-
bipyridine and iridium(III) bis-phenylpyridine complexes with 1,5-diarylbiguanides,
orotic acid, pyridylmethylenehydantion, and diaminotriazine-pyridyltriazole ligands are
presented, along with our progress towards obtaining complex-complex co-crystals.[3,
4]
Figure.1. X-ray crystal structure of palladium(II) phenylpyridine diarylbiguanide co-crystallised with the
complementary organic molecule dimethylaminonaphthalimide.
[1] S. Bhattacharya, K. S. Peraka and M. J. Zaworotko, in Co-crystals: Preparation, Characterization
and Applications, The Royal Society of Chemistry, London, United Kingdom, 2018
[2] G. R. Desiraju, J. J. Vittal and A. Ramanan, Crystal Engineering, Co-Published with Indian Institute
of Science (IISc), Bangalore, India, 2011.
[3] A. P. McKay, G. E. Shillito, K. C. Gordon and D. A. McMorran, CrystEngComm, 2017, 19, 7095-
7111
[4] A. P. McKay, J. I. Mapley, K. C. Gordon, D. A. McMorran, Chem. Asian J. 2019, 14 (8), 1194-1203.
Poster Presentations
76 12th Australasian Organometallics Meeting
A Dipolar Molecular Switch for Nonlinear Optics
Mahbod Morshedi, Katy A. Green, Marie P. Cifuentes, Mark G. Humphrey*
Research School of Chemistry, Australian National University, ACT 2601, Australia
Email: [email protected]
Designing and creating multistate switches that respond to different stimuli (light,
chemicals, etc.) is a current challenge in the push to replace silicon-based logic gates
and other computational components. The applications can potentially be even more
diverse if switching exploits not only the linear properties of light but also the nonlinear
properties. The dipolar dithienylperfluorocyclopentene (DTE) unit has been
conjugated with electrochemical and chemical switching modules to produce
centrosymmetric molecules with a large number of switchable nonlinear optical
states.[1] Extensions of this research to dipolar examples will be described.
Six states of the dipolar Ru-DTE switch.
References
[1] K. A. Green, M. P. Cifuentes, T. C. Corkery, M. Samoc, M. G. Humphrey, Angewandte Chemie International Edition 2009, 48, 7867-7870.
Poster Presentations
77 12th Australasian Organometallics Meeting
Synthesis and characterization of bismuth (III)
phosphonates as antimicrobial polymeric materials
Shazia Nawaz, Liam Stephens, Kei Saito, Phil Andrews*
School of Chemistry, Monash University
Microbes are threatening human safety and well-being resulting in a number of
infectious diseases.1 This is an alarming situation because a resistant infection can
cause deaths, can spread to others imposing a lot of costs to society as well as
individuals. Three hundred million premature deaths are estimated by 2050 to be
caused by antibiotic resistance if the problem is not addressed properly.2
The compounds of Bismuth (III) have been used for the treatment of skin conditions,
gastrointestinal infections and disorders.3 We have synthesized bismuth (III)
phosphonate complex BiPhL that is insoluble in common solvents. The complex
exhibits antibacterial activity in the solid state towards Staphylococcus aureus (S.
aureus), Methicillin-resistant Staphylococcus aureus (MRSA), Acinetobacter
baumannii (A. baumannii) and Pseudomonas aeruginosa (P. aeruginosa).
Figure 1- General synthetic route of bismuth (III) vinyl phosphonate formation
Antimicrobial polymers are of considerable attention both in industrial and academic
research. Vinyl phosphonic acid was polymerised using different azo initiators and the
resultant polymer reacted with triphenyl bismuth. Polymer itself and polymeric bismuth
compounds also display antibacterial activity against both Gram positive and Gram
negative bacteria. Polymeric bismuth compound is also insoluble in common solvents.
These compounds have been characterised using Gel permeation chromatography
(GPC), solid state NMR spectroscopy, IR and elemental analysis.
References
(1) Huang, K.-S.; Yang, C.-H.; Huang, S.-L.; Chen, C.-Y.; Lu, Y.-Y.; Lin, Y.-S. Recent Advances in
Antimicrobial Polymers: A Mini-Review. Int. J. Mol. Sci. 2016, 17 (9).
(2) WHO | Antimicrobial Resistance. WHO 2018. (3) Paladini, F.; Pollini, M.; Sannino, A.; Ambrosio, L. Metal-Based Antibacterial Substrates for
Biomedical Applications.
Poster Presentations
78 12th Australasian Organometallics Meeting
A one-pot route to thioamides and Amidines discovered by
fundamental gas-phase studies
Asif Noor1, Yang Yang1, J. Li1, G. N. Khairallah1, Z Li1, H Ghari2, A. J. Canty3, A. Ariafard2*, P. S. Donnelly1* and R. A. J. O’Hair1*
1School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia.
2Department of Chemistry, Faculty of Science, Central Tehran Branch, Islamic Azad University, Shahrak Gharb, Tehran, Iran.
3School of Physical Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
Thioamides and amidines are useful compounds for applications in organic synthesis
and medicinal chemistry. A simple “one pot” palladium mediated synthesis of
thioamides and amidines from aromatic carboxylic acids (Figure 1) will be presented.
The methodology was developed using a combination of gas-phase multi-stage mass
spectrometry experiments and DFT calculations. The gas phase chemistry was
extended to the condensed phase, where the individual steps were examined via 1H
NMR spectroscopy before optimising the “one pot” method. A total of eight thioamides
and six amidines were synthesized and fully characterized, including via X-ray
crystallography.
This new chemistry takes advantage of the isoelectronic analogy to open up a new
class of reactions, coined CO2ExIn (ExIn = Extrusion-Insertion) that could be broadly
applicable to other substrates. These results highlight the emergence of fundamental
gas-phase studies to direct the discovery of new reactions for use in organic synthesis.
Figure 1 Palladium catalysed decarboxylative transformation of aromatic carboxylic acids into
thioamides
Poster Presentations
79 12th Australasian Organometallics Meeting
A New Approach to Design MOF Based Catalysts
R. A. J. O’Hair*,[b] A. Mravak, [b] M. Krstić [b] and V. Bonačić-Koutecky*[b]
[a] School of Chemistry, The University of Melbourne, Australia
[b] Center of Excellence for Science and Technology, University of Split, Croatia.
We have been using mass spectrometry (MS) based methods and DFT calculations
to design transition metal catalysts from the ground up for the selective
decarboxylation of formic acid,[1] a reaction of considerable interest for hydrogen
storage applications and in situ generation of H2. Here we describe a new conceptual
approach for the design of a heterogeneous metal-organic framework (MOF) catalyst
based on UiO-67 for the decomposition of formic acid. Models for the {CuH} reactive
catalytic site at the organic linker are assessed. In the first model system, MS
experiments and DFT calculations on a fixed charge bathophen ligated copper hydride
complex, [(phen*)Cu(H)]2-, were used to demonstrate that it selectively decomposes
formic acid into H2 and CO2 via a two step catalytic cycle. In the first step liberation of
H2 to form the carboxylate complex, [(phen*)Cu(O2CH)]2- occurs, which in the second
step selectively decomposes via CO2 extrusion to regenerate the hydride complex.
DFT calculations on four other model systems showed that changing the catalyst to
neutral [(LCu(H)] complexes or embedding it within a MOF results in mechanisms
which are essentially identical. Thus catalytic active sites located on the organic linker
of a MOF appear to be close to a gas-phase environment, thereby benefitting from the
favorable characteristics of gas-phase reactions and validating the use of gas-phase
models to design new MOF based catalysts.
References
[1] A. Zavras, et al., Nat. Commun. 2016, 7, 11746; A. Zavras, et al., Dalton Trans. 2016, 45, 19408; A.
Zavras, et al., ChemCatChem 2017, 9, 1298; M. Krstić, et al., ChemCatChem 2018, 10, 1173.
[2] R.A.J. O’Hair, et al., ChemCatChem 2019, 11, 2443–2448.
Poster Presentations
80 12th Australasian Organometallics Meeting
Selenium functionalised metal-carbon chains –
Alkynylselenolatoalkylidynes (LnMC–Se–CCR)
Chee S. Onn, Benjamin J. Frogley, Anthony F. Hill*
Research School of Chemistry, Australian National University.
The reactions of [W(≡CBr)(CO)2(Tp*)] (Tp* = hydrotris(3,5-dimethylpyrazol-1-
yl)borate) with lithium alkynylselenolates LiSeC≡CR (R = SiMe3, SiiPr3, nBu, tBu, Ph,
p-tolyl) afford the alkynylselenolatoalkylidyne complexes [W(≡CSeC≡CR)(CO)2(Tp*)].
Desilylation of the SiMe3 complex furnishes the parent [W(≡CSeC≡CH)(CO)2(Tp*)],
which may be further derivatised by deprotonation and treatment with
triphenylcarbenium or triphenyltetrel chlorides to give mixed-heteroatom products
[W(≡CSeC≡CEPh3)(CO)2(Tp*)] (E = C, Si, Ge, Sn, Pb).
This procedure extends to dichlorosilanes, whereby the unusual bimetallic complexes
[(Tp*)(CO)2W≡CSeC≡CSiRR′C≡CSeC≡W(CO)2(Tp*)] (R, R′ = Ph, CH3) are obtained,
bridged by unsaturated units interrupted by two different main-group heteroatoms.
Finally, the trimetallic analogues, [{(Tp*)(CO)2W(≡CSeC≡C)}3SiR] (R = Ph, Et), may
be prepared in the same manner from appropriate organotrichlorosilanes.
Professor Dr Anthony F. Hill
RESEARCH SCHOOL OF CHEMISTRY, BUILDING NO. 137 T: +61 2 6125 8577 AUSTRALIAN NATIONAL UNIVERSITY E: [email protected]
CANBERRA ACT 0200 AUSTRALIA http://chemistry.anu.edu.au
CRICOS Provider No. 00120C
April 9th 2019 To the Editors
Dalton Transactions
We would appreciate your consideration of the accompanying manuscript for publication as a
full paper in Dalton Transactions.
Some years ago we described the (only) alkynylselenolatocarbyne complexes
[Mo(≡CSeC≡CR)(CO)2(Tp*)] (R = CMe3, SiMe3, p-tolyl) which feature both Mo≡C and C≡C triple
bond bound to a selenoether linkage. Perhaps not surprisingly, the Mo≡CSeC≡C- linkage offers a
number of functionalities capable of undergoing unusual transformations. In the current paper we not
only extend this chemistry to the first tungsten derivatives (R = SiMe3, SiiPr3, nBu, tBu, Ph, p-tolyl)
but also investigate the possibility of constructing more elaborate bi- an tri-nuclear examples that
emerge from functionalisation of the parent complex [W(≡CSeC≡CH)(CO)2(Tp*)] which is in turn
accessible via desilylation of the SiMe3 derivative. Deprotonation of the parent allows access to
[W(≡CSeC≡CLi)(CO)2(Tp*)] (in situ) which undergoes nucleophilic substitution with a range of
group 14 electrophiles to afford inter alia the entire tetrel substituted series
[W(≡CSeC≡CAPh3)(CO)2(Tp*)] (A = C, Si, Ge, Sn, Pb) and polynuclear silanes
R2Si{C≡W(CO)2(Tp*)}2 and RSi{C≡W(CO)2(Tp*)}3 (R = Me, Et, Ph).
We expect that the work will interest those in the filds of carbyne chemistry, carbon-wire
chemistry, structural chmistry and the interface of transition and main-group metal chemistries.
Yours faithfully,
Anthony F. Hill
Page 2 of 71Dalton Transactions
Poster Presentations
81 12th Australasian Organometallics Meeting
Electron transfer processes and mixed-valence chemistry: studies with metal complexes featuring carbon-rich
ligands Parvin Safari,a Simon Gückel,b Josef Gluyas,a Martin Kaupp,b Paul J. Lowa*
a School of Molecular Sciences, The University of Western Australia
b Institut fur Chemie, Technische Univesität Berlin
Electron transfer is a ubiquitous process in chemistry, and the exchange of an electron
between two sites might be considered the most elementary of all chemical reactions.
Mixed-valence (MV) complexes {LxMn}{-bridge}(M(n+1)Lx} in which two redox centres
{MLn}, identical in every way except their formal oxidation state, are linked by a
bridging ligand have served as powerful model systems through which to study the
fundamentals of the intramolecular electron exchange reaction.
General scheme for complexes containing carbon rich bridges
In turn, a deeper understanding of the electronic structure and charge distribution in
these systems has allowed the development of a range of molecular optoelectronic
materials. Conventionally, the electronic character of a MV complex and degree of
‘electronic coupling’ between the redox sites through the bridge is determined using
the relationships developed by Hush and described within the general framework of
Marcus-Hush theory.
However, whilst appealing, the analysis of MV compounds using the Hush model is
non-trivial in many cases, with the critical IVCT band often overlapped with other
electronic transitions and, in the case of strongly coupled / highly delocalised systems,
asymetrically shaped. Furthermore, these analyses are typically based on the
assumption that the MV complex can be adequately described by one single, dominant
molecular conformation while MV complexes are often present as a complex
conformational mixture, with member differing by the relative orientation of the metal
end-caps around the M-bridge-M’ axis. As electronic structure depends on orbital
overlap along the M-bridge-M molecular backbone, these conformational factors can
play a significant role in the description of the electronic structure of the compound in
solution.
In this poster, we will represent a range of carbon-rich bridged bi- and multi-metallic
complexes that are designed to carry spectroscopic probes to permit the development
of new strategies for the experimentally convenient study of electron transfer
processes.
Poster Presentations
82 12th Australasian Organometallics Meeting
Reactivity of Newly Discovered Trans-Difluorogold(III)
Complexes
Lachlan T. Sharp-Bucknall, Dr. Jason Dutton*
School of Molecular Sciences, La Trobe University
Development of new gold fluoride species is of interest because of their rarity and
potential to catalytically generate fluorinated molecules.
Our group has recently produced a group of trans difluorogold(III) complexes that are
supported by N-ligands. These complexes are stable, easily isolable and are the first
examples of trans gold difluorides supported by N-ligands. [1]
Due to the general rarity and relative novelty of these complexes, their reactivities are
yet to be substantially investigated. Consequentially, this work seeks to cover these
investigations by following the reactivities of our complexes with various substituents
such as carbenes, alkynes and trimethylsilyl functionalised species.
References
[1] M. Albayer, R. Corbo and J. L. Dutton, Chem. Commun., 2018, 54(50), 6832
Poster Presentations
83 12th Australasian Organometallics Meeting
Experimental and Theoretical Properties of Low-Oxidation
State Aluminium Amidinate Complexes
Cory D. Smith, Cameron Jones*
School of Chemistry, Monash University
The chemistry of aluminium in the +1 oxidation state is vastly unexplored, with only
two neutral monomeric species having been fully characterised.[1-2] The most widely
used of these is a (NacNac)Al: (NacNac = β-diketiminiate) species synthesised by
Roesky in 2003. This compound has been shown by various groups to oxidatively add
a range of σ- and π-bonds.[3] Additionally, Aldridge and Goicoechea recently reported
the synthesis of an aluminium(I) anion, formed through reduction of an aluminium
iodide species bearing a NON pincer ligand.[4]
Current work within the Jones group is aimed at producing Al(I) species bearing
amidinate backbones containing bulky motifs, which have previously been shown to
stabilise the first known dimeric strontium hydride species, for example.[5] Additionally,
the use of a bulky aliphatic amine will hopefully enable the amidinate to better stabilise
a low-oxidation state aluminium centre.
[1] Cui, C.; Roesky, H. W.; Schmidt, H.-G.; Noltemeyer, M.; Hao, H.; Cimpoesu, F. Angew. Chemie 2000, 39 (23), 4274–4276. [2] Xiaofei Li; Xiaoyan Cheng; Haibin Song, and; Cui*, C. Organometallics 2007, 26, 1039-1043 [3] Chu, T.; Korobkov, I.; Nikonov, G. I. J. Am. Chem. Soc. 2014, 136 (25), 9195–9202.
[4]Hicks, J.; Vasko, P.; Goicoechea, J. M.; Aldridge, S. Nature 2018, 557 (7703), 92–95.
[5] de Bruin-Dickason, C. N.; Sutcliffe, T.; Alvarez Lamsfus, C.; Deacon, G. B.; Maron, L.; Jones, C.
Chem. Commun. 2018, 54 (7), 786–789.
Poster Presentations
84 12th Australasian Organometallics Meeting
Superphenylphosphines: Nanographene-based Ligands
that Direct Coordination and Bulk Assembly
Jordan N. Smith,1,2 James M. Hook,3 Nigel T. Lucas*1,2
1Department of Chemistry, University of Otago, Dunedin, New Zealand 2MacDiarmid Institute for Advanced Materials and Nanotechnology, New Zealand
3Mark Wainwright Analytical Centre, University of NSW, Sydney, Australia
Phosphines are ubiquitous throughout coordination and organometallic chemistry, and
are common supporting ligands in transition metal catalysis. An attraction of tertiary
phosphines is the ability to tune their electronic and steric properties. While
trialkylphosphines are some of the most electron-donating examples, aryl phosphines
tend to be more easily handled and are sufficiently strong donors for many
applications. Furthermore, phenyl/aryl groups on phosphine ligands in metal
complexes can play a major role in the driving the supramolecular order.1
Large polycyclic aromatic hydrocarbons have gained considerable interest because of
their electronic and optical properties, and the strong π-interactions that direct their
assembly into columnar stacks.2 One such nanographene is hexa-peri-
hexabenzocoronene (HBC), consisting of 42 carbon atoms in 13 fused rings; the
hexagonal geometry and stability comparable to benzene has led to HBC being
described as ‘superbenzene’ (Fig. 1). As part of our research into nanographene-
based ligands, we have synthesized a series of ‘superphenylphosphines’.3 The
coordination of these phosphines to several different metals has been investigated,
along with the role the HBC fragment plays on coordination geometry and driving
assembly in the crystalline phase.
Figure 1. Diagrams of superbenzene, superphenylphosphines 1 and 3, and the crystallographically-
determined structure of the complex PdCl2(1)2.
References
[1] I. Dance, M. Scudder, CrystEngComm, 2009, 11, 2233.
[2] K. Müllen, ACS Nano., 2014, 8, 6531.
[3] J. N. Smith, J. M. Hook and N. T. Lucas, J. Am. Chem. Soc, 2018, 140, 1131.
Poster Presentations
85 12th Australasian Organometallics Meeting
Selective Activation of Alkynes through Cumulene
Intermediates
Rachel R. Steen a,b, Michael Hall b, Jason Lynam a*, Paul Low b*
a Department of Chemistry, University of York, UK, b School of Molecular Science,
University of Western Australia
Transition metal complexes are important in the synthesis of various pharmaceutical
and agrochemical products and can be used to facilitate the formation of new C-C and
C-heteroatom bonds. Cumulenes, chains of sp-hybridised carbon atoms, terminated
by an sp2-hybridised carbon atom and often a metal ligand fragment, are of particular
interest due to their unique reactivity; electrophilic attack is more likely to occur at even
numbered carbons and nucleophilic attack at the odd1. However they are difficult to
synthesise once the chain length extends beyond 4 atoms.
Previous work2 suggested that aromatic spacer groups may be used to stabilise a
cumulene chain, and DFT studies showed a cumulenic intermediate in the reaction of
the vinylidene trans-[Ru(=C=CHC6H4-4-C≡CH)Cl(dppm)2]BF4 and [NnBu4]Cl. Here, a
quinoidal cumulene has been stabilised in the coordination sphere of a ruthenium and
trapped through reaction with nucleophiles at the seventh carbon.
References
1 C. Bruneau and P. Dixneuf, Eds., Metal Vinylidenes and Allenylidenes in Catalysis, Wiley‐
VCH, Weinheim, Germany, 2008.
2 S. G. Eaves, S. J. Hart, A. C. Whitwood, D. S. Yufit, P. J. Low and J. M. Lynam, Chem.
Commun., 2015, 51, 9362–5.
Poster Presentations
86 12th Australasian Organometallics Meeting
Synthesis of Novel Bismuth Tetrazole Thiolate Complexes
as Potential Antimicrobials
Liam J. Stephens, Tom H. Moran, Rebekah N. Duffin, Melissa V. Werrett, Phil C.
Andrews*
School of Chemistry, Monash University
Antibiotic resistant bacteria are becoming increasingly common. New resistance
mechanisms are continually being discovered, with new genes and vectors for
transmission of resistance identified on a regular basis.[1] This inexorable rise of
bacterial resistance has been further intensified by the lack of new antibiotics being
developed over the last 20 years. Organometallic Bismuth (Bi) compounds offer an
attractive alternative to the typically used organic molecules in combating antibiotic
resistance, due in large to their limited toxicity against human cells (as demonstrated
by pepto-bismol used to treat gastrointestinal infections).
Since their discovery in 1885, the tetrazole moiety has been identified as a key
functionality in a host of clinically used pharmaceuticals including anti-inflammatory,
antifungal, anticancer and antibiotics.[2] With this knowledge in mind, we explored the
possibility of developing tetrazole containing Bi complexes and have since
synthesised, and fully characterised, 18 new derivatives of this kind. A number of these
novel compounds have demonstrated excellent antibiotic activity against a broad
spectrum (Gram positive and Gram negative) of bacteria. Further biological assays
will be discussed including time-kill assays, which revealed the bacteriostatic nature
of these novel compounds.
Figure 1: The novel Bismuth tetrazole thiolate complexes that have been synthesised and tested
against a broad spectrum of bacteria.
References
[1] J. M. A Blair, L. J. V Piddock, Molecular Mechanisms of Antibiotic Resistance. Nature Reviews
Microbiology, 13, 42-51, (2015).
[2] V. A. Ostrovskii, R. E. Trifonov, Developments in Tetrazole Chemistry 2009-16. Advances in
Heterocyclic Chemistry, 123, 1-62, 2017.
Poster Presentations
87 12th Australasian Organometallics Meeting
Biological Studies of a Molybdenum based Cyanide Poisoning Antidote
Sigridur G. Suman1*, Linda A. Hancock1, Johanna M. Gretarsdottir1, Stefan Sturup2, Ian H. Lambert3
1Science Institute, University of Iceland, Dunhagi 3, 107 Reykjavik, Iceland.
2University of Copenhagen, Department of Pharmacy, Universitetsparken 2, 2100 Copenhagen Ø, Denmark.
3University of Copenhagen, Department of Biology, Universitetsparken 13, 2100 Copenhagen Ø, Denmark
Cyanide poisoning antidotes function to prevent cyanide from permanently inhibit cytochrome c oxidase who is primary lethal target [1]. Although these antidotes are efficacious, their donwsides prevent their use for emergency treatment of cyanide poisoning [2]. Since cyanide is an endogenous molecule [3], a physiological mechanism to transform cyanide into a non-toxic thiocyanate involves the rhodanase enzyme [4].
Molybdenum sulfur complex salts are capable of converting cyanide to thiocyanate [5]. Selected compounds were evaluated for cytotoxicity in three different cancer cell lines [6]. The compounds proved to have low cytotoxicity compared to cisplatin and even less so for alkali salts compared to tetraalkylammonium salts. Uptake and distribution in cells showed the compounds enter the cells and distribution was confirmed in cytosol, nucleus and mitochondria [5]. Toxicity in vivo was studied in a mouse model showing the compounds are relatively safe [7]. Pharmacokinetic data revealed a selected compound enters the bloodstream rapidly and exits in a timely manner [7]. Inhalation study in a mouse model showed modest efficacy against a challenge [7]. The presentation will summarize these findings and discuss their relevance for an emergency antidote to treat cyanide poisoning.
Financial support by the Icelandic Technology Development Fund (Rannís Tækniþróunarsjóður) grant nr. 164784 and by The Icelandic Centre of Research grant nr 140945 is gratefully acknowledged.
References
[1] H. B. Leavesley, L. Li, K. Prabhakaran, J. L. Borowitz, and G. E. Isom, “Interaction of Cyanide and Nitric Oxide with Cytochrome c Oxidase: Implications for Acute Cyanide Toxicity”. Toxicological Sciences 2008, 101(1), pp. 101-111.
[2] S. G. Suman, J. M. Gretarsdottir, “Chemical and Clinical Aspects of Metal Containing Antidotes for Poisoning by Cyanide”, Met. Ions Life Sci., Eds. A. Sigel, E. Freisinger, R. K. O. Sigel, Walter de Gruyter GmbH, Berlin, Germany, 2019, (19), pp. 359-391.
[3] P. G. Gunasekar, J. L. Borowitz, J. J. Turek, D. A. V. Horn, G. E. Isom, “Endogenous Generation of Cyanide in Neuronal Tissue: involvement of a Peroxidase System”. J. Neurosci. Res. 2000, 61, pp. 570-575.
[4] K. R. Leininger, J. W., The Mechanism of the Rhodanese-catalyzed Thiosulfate Cyanide Reaction. J. Biol. Chem. 1967, 243 (April 25), pp. 1892-1899.
[5] J. M. Gretarsdottir, “Syntheses of new molybdenum-sulfur complexes: Catalytic transformation of cyanide to thiocyanate and in vitro biological studies“, PhD Thesis, University of Iceland, 2018.
[6] Gretarsdóttir, J. M, Bobersky, S., Metzler-Nolte, N., Suman, S. G., “Cytotoxicity Studies of Water Soluble Coordination Compounds with a [Mo2O2S2]2+ Core” J. Inorg. Biochem. 2016, 160, pp. 166-171.
[7] L. A. Hancock, “In vivo Analyses of a Mo2O2S4-Based Metallodrug”, MS Thesis, University of Iceland, 2018.
Poster Presentations
88 12th Australasian Organometallics Meeting
A new rotational isomer of bis(pentafluorophenyl)mercury
[Hg(C6F5)2]
Yu Qing Tan, Niko T. Flosbach, Céline Leonhardt, Glen B. Deacon*, Victoria Blair,
Peter C. Junk
School of Chemistry, Monash University, Clayton 3800, Australia.
College of Science and Engineering, James Cook University, Townsville 4811, Qld,
Australia.
It has been found that bis(pentafluorophenyl)mercury, possesses a previously
unknown second rotational isomer. Both rotamers yield identical IR and NMR spectra
and distinction between them can only be ascertained from their X-ray structures and
microscopic imaging (Figure 1).
X-ray structure (reported rotamer): orthorhombic, space group P212121, a =5.762(1),
b=10.645(1), c= 20.296(2) Å.1 Rotational angle of the arene rings: 58.03°.
X-ray structure (new rotamer): monoclinic, space group P21/n, a= 11.7060(3), b=
7.8531(2), c= 13.5429(4) Å. Rotational angle of the arene rings: 74.62°.
Figure 1: Side by side comparison of reported Hg(C6F5)2 crystals and the new
rotational isomer of Hg(C6F5)2
The new conformer was attained from a variety of methods. Recrystallization of
Hg(C6F5)2 was done by dissolving Hg(C6F5)2 in n-hexane and heating. Upon standing
for two weeks, block-like crystals were achieved in situ.
References
1 D. L. Wilkinson, J. Reide, G. Müller, Z. Naturforsch, 1991, 46b, 285-288.
Poster Presentations
89 12th Australasian Organometallics Meeting
Synthesis, Characterization and Biological Activity of
Select [Pt(2-pyridyl-1,2,3-triazole)2]2+ “Click” Complexes
James E. Foote,1,2 Dan Preston,1,3 Roan Vasdev,3 Synøve Scottwell,1 Quinn van
Hilst,1,2 Greg I. Giles,3 Heather J. L Brooks,2 James D. Crowley.1,*
1 Department of Chemistry, University of Otago, Dunedin, New Zealand
2 Department of Microbiology and Immunology, University of Otago, Dunedin, New
Zealand
3 Department of Pharmacology and Toxicology, University of Otago, New Zealand
While the biological importance of platinum complexes has been demonstrated via
their use in anti-cancer therapy, platinum complexes also possess unique and
interesting activity against bacteria.[1] Recently, Crowley and co-workers reported the
synthesis of a pair of square planar pyridyl-triazole (pytri) platinum(II) complexes that
exist solely as single isomers due to interligand hydrogen bonding.[2] As these
complexes can be readily generated via the Cu(I)-catalysed azide-alkyne
cycloaddition (CuAAC) reaction with differing appending groups, they allow for the
generation of a family of complexes. Previous work in the Crowley group has shown
that the antibacterial potency of a mono-nuclear pytri system can be focused by
varying the length of the appended alkyl chain.[3] As such, we set out to synthesise a
family of square planar [Pt(pytri)2]2+ complexes with appended alkyl or aromatic
substituents and investigate their antimicrobial properties. The complexes were
characterized via 1H and 13C NMR spectroscopy, ESI-MS and elemental analysis.
Their antibacterial activity was determined against S. aureus (ATCC 25923) and E.
coli (ATCC 25922), as well as cytotoxicity data gathered for the lead complexes
against a selection of cell lines (A549 (lung cancer), MDA MB231 (breast cancer),
WM266 (human melanoma) and HDFa (normal human dermal fibroblasts)).
Preliminary mode of action studies as well as screening against a wider spectrum of
bacteria (MRSA (MR 4393 and MR 4549), M. smegmatis and A. calcoaceticus) was
performed for the lead complex identified.
Figure 1: Synthesis of platinum(II) complexes: (i) (a) NaN3, DMF/H2O (4:1), 110oC, 1 h, (b) sodium ascorbate, CuSO4, RT, 12 h; (ii) (a) [Pt(DMSO)2Cl2], AgNO3, 10 min,(b) absence of light, 85oC, 12 h.
[1] (a) Rosenberg, B.; Van Camp, L.; Krigas, T., Nature 1965, 205 (4972), 698-699; (b) Gibson, D., J. Inorg. Biochem. 2019, 191, 77-84. [2] Preston, D.; Tucker, R. A. J.; Garden, A. L.; Crowley, J. D., Inorg. Chem. 2016, 55 (17), 8928-8934. [3] Kumar, S. V.; Scottwell, S. O.; Waugh, E.; McAdam, C. J.; Hanton, L. R.; Brooks, H. J.; Crowley, J. D., Inorg. Chem. 2016, 55 (19), 9767-9777.
Poster Presentations
90 12th Australasian Organometallics Meeting
Catalytic activity of N-heterocyclic carbene Ag(I) amides
Daniel Van Zeil, John Kelly, Aaron Boutland, Victoria Blair*
School of Chemistry, Monash University
Within the group 11 “coinage” metals, silver is often overlooked due to its instability
under ambient light and growing interest in gold analogues of established copper
catalysed reactions[1]. Silver is most often used in Lewis acid catalysis in the form of a
silver salt, however, in a recent study by Kobayashi[2] the use of copper and silver
amides as catalysts was explored with [3+2] cycloaddition reactions. With this being
the only example of silver amide catalysis in the literature, this area of chemistry is
primed for exploration
Our research group is currently exploring the synthesis and characterisation of a
library of NHC silver(I) amides and testing their catalytic activity via simple hydro-
functionalisation reactions. By changing the bulkiness, aromaticity and chirality of both
the R groups on the NHC carbene and the R’ groups on the amide, we hope to
optimise catalytic activity and improve light stability.
Figure 1: Target NHC stabilised silver(I) amide complex and candidate R groups.
References
[1] Díez-González, S. and S. P. Nolan (2008). "Copper, Silver, and Gold Complexes in Hydrosilylation
Reactions." Accounts of Chemical Research 41(2): 349-358.
[2] Yamashita, Y. and Kobayashi, S. 2013. Metal Amides as the Simplest Acid/Base Catalysts for Stereoselective Carbon–Carbon Bond‐Forming Reactions. Chemistry - A European Journal. 19, 29 (2013), 9420–9427.
R = = R’
Poster Presentations
91 12th Australasian Organometallics Meeting
Deep Blue Organic Light Emitting Diodes Based on N-
Heterocyclic Carbene Platinum(II) Complexes
Koushik Venkatesan*
Department of Molecular Sciences, Macquarie University, North Ryde, NSW 2109
New efficient light-emitting materials are crucial for applications in sensors,
photoelectronic devices, and optical devices. Transition metal complexes have been
employed as triplet emitters for application in phosphorescent organic light emitting
devices (PhOLEDs). [1, 2] Transition metals such as iridium and platinum with suitable
ligands allow for tailoring the photoluminescent properties. Achieving high stability,
quantum efficiency and specific chromaticity of platinum(II) complexes present a major
challenge in this field. While a large variety of green and red emitters with excellent
luminescent properties is known, the focus of the ongoing research lies on deep blue
emitting complexes. In this work, we demonstrate that deep blue PHOLEDs with high
external quantum efficiency can be achieved through a rational combination of ligands
around the platinum(II) centre.[3]
References
[1] M. A. Baldo, D. F. O’Brien, M. E. Thompson, S. R. Forrest, Phys. Rev. B 1999, 60, 14422-14428.
[2] Y. Chi, P.-T. Chou, Chem. Soc. Rev. 2010, 39, 638-655.
[3] M. Bachmann, Y. Zhang, C.-C. Wu, O. Blacque, K. Venkatesan, Manuscript under preparation.
Poster Presentations
92 12th Australasian Organometallics Meeting
Synthesis, Linear Optical, and Second-/Third-Order NLO
Properties of Porphyrin-Bridged Push-Pull Ruthenium
Complexes
Huan Wang, Mahbod Morshedi, Cristóbal Quintana, Mark G. Humphrey*
Research School of Chemistry, Australian National University, Canberra, ACT 2601
The synthesis of two porphyrin-bridged push-pull ruthenium complexes (13, 16), as
well as their organic counterpart (9), are reported. These organic and organometallic
chromophores show large quadratic and cubic nonlinear optical (NLO) properties. The
electrochemical properties of 13 and 16 were assessed by cyclic voltammetry, and the
linear optical, second- and third-order NLO properties were measured by UV-vis,
hyper-Rayleigh scattering studies at 1064 nm, broad spectral range femtosecond Z-
scan studies, and optical limiting studies. The Ru complexes enhance the β value by
almost 3 times compared to that of the non-Ru-containing counterparts. However, the
introduction of a meso-substituted porphyrin-based bridge has a limited effect on
quadratic and cubic NLO responses compared to phenylene bridge-based Ru
complexes [1], which can be explained by the strong linear absorption of the porphyrin
at the measurement wavelength. Optical limiting measurements showed reverse
saturable absorption properties of 13 and 16.
References
[1] Organometallic Complexes for Nonlinear Optics. 43. Quadratic Optical Nonlinearities of Dipolar
Alkynylruthenium Complexes with Phenyleneethynylene/Phenylenevinylene Bridges
Luca Rigamonti, Bandar Babgi, Marie P. Cifuentes, Rachel L. Roberts, Simon Petrie, Robert Stranger,
Stefania Righetto, Ayele Teshome, Inge Asselberghs, Koen Clays, and Mark G. Humphrey
Inorganic Chemistry 2009 48 (8), 3562-3572
DOI: 10.1021/ic801953z
Poster Presentations
93 12th Australasian Organometallics Meeting
Desulfination versus decarboxylation as a means of
generating three- and five- coordinate organopalladium
complexes [(phen)nPd(C6H5)]+ (n = 1 and 2) to study their
fundamental bimolecular reactivity.
Zilin Wang[1], Yang Yang[1], Paul S. Donnelly[1], Allan J. Canty[2]*, Richard A. J.
O’Hair[1]*
[1] School of Chemistry, The University of Melbourne
[2] School of Natural Sciences – Chemistry, University of Tasmania
Routes to the formation of the 1,10-phenanthroline (phen) ligated organopalladium
complexes [(phen)Pd(C6H5)]+ and [(phen)2Pd(C6H5)]+ via thermal extrusion of CO2 or
SO2 from mono-nuclear, mono-carboxylate or sulfinate complexes
[(phen)nPd(O2XC6H5)]+ (X = C or S; n = 1 and 2) are examined using a combination of
low energy collision induced dissociation (CID) experiments in an ion trap mass
spectrometer and DFT calculations. [(phen)Pd(C6H5)]+ is formed from both
[(phen)Pd(O2CC6H5)]+ and [(phen)Pd(O2SC6H5)]+ (eq. 1) but only
[(phen)2Pd(O2SC6H5)]+ fragments to form [(phen)2Pd(C6H5)]+ (eq. 2). In contrast,
[(phen)2Pd(O2CC6H5)]+ fragments via loss of a phen ligand to form
[(phen)Pd(O2SC6H5)]+ (eq. 3). The experimental findings are supported by DFT
calculations, which show that the barriers associated with the desulfination reactions
are lower than those for the decarboxylation reactions. Of the organopalladium cations
[(phen)Pd(C6H5)]+ and [(phen)2Pd(C6H5)]+, only the three-coordinate complex reacts
with pyridine via a ligand coordination reaction to yield [(phen)Pd(C6H5)(NC5H4)]+ and
with formic acid via an acid-base reaction to form [(phen)Pd(O2CH)]+. DFT calculations
highlight that the former reaction is exothermic by 44 kcal/mol while the later reaction
proceeds via a favorable six-centered transition structure.
[(phen)Pd(O2XC6H5)]+ → [(phen)Pd(C6H5)]+ + XO2 (1)
[(phen)2Pd(O2XC6H5)]+ → [(phen)2Pd(C6H5)]+ + XO2 (2)
→ [(phen)Pd(O2XC6H5)]+ + phen (3)
(X = C or S)
Poster Presentations
94 12th Australasian Organometallics Meeting
Early transition metal poly(methimazolyl)borate complexes
Steven S. Welsh, Anthony F. Hill*
ANU Research School of Chemistry, Australian National University, Sullivans Creek
Road, Acton, ACT, 2601
Poly(methimazolyl)borates HχB(mt)4-χ are a class of chelating ligands which have the
ability to bind to a metal centre via two or three ‘soft’ sulphur donor atoms. They
possess excellent donor properties for late transition metals, in accordance with the
hard-soft acid-base concept, where nigh-ideal ‘soft acid/soft base’ compatibility is
observed.
However, a growing body of evidence suggests that binding to early ‘hard’ transition
metals in high oxidation states may not only be viable, but also more readily achievable
than previously thought. The first such exemplar species, [M(=NR)Cl2{HB(mt)3}] (M =
Nb, Ta; R = C6H3iPr2-2,6; mt = methimazolyl), Cp[HB(mt)3]ZrCl2 and
[Ti(=NCMe3){H2B(mt)2}2], display a range of poly(methimazolyl)borate coordination
modes and demonstrate the first signs of a field of chemistry which up until now has
been untapped. [1-3]
Initial efforts to synthesise early transition metal poly(methimazolyl)borates were
significantly hindered. In an effort to overcome many of these hurdles, our current work
hopes to improve on the synthetic methodologies which currently exist, and to develop
new synthetic pathways which will ultimately lead to a greater diversity and
understanding in this field.
Simplified molecular structures of Cp[HB(mt)3]ZrCl2[2] and [Ti(=NCMe3){H2B(mt)2}2][3].
References
[1] A. F. Hill, A. D. Rae, M. K. Smith, Inorg. Chem., 2005, 44, 7316
[2] D. Buccella, A. Shultz, J. G. Melnick, F. Konopka, G. Parkin, Organometallics, 2006, 25, 5496
[3] A. F. Hill, M. K. Smith, Dalton Trans., 2006, 28
B1
S3
S1
S2
Zr1
S22 S21
S12 S11
B2
B1
Ti1
Poster Presentations
95 12th Australasian Organometallics Meeting
A novel transition-metal assisted approach to amide
synthesis directed by mechanistic studies
Yang Yang, Paul S. Donnelly, Allan J. Canty, Richard A. J. O’Hair*
School of Chemistry and Bio21 Molecular Science and Biotechnology Institute,
University of Melbourne
Amides are a basic and highly important class of compounds with a variety of biological
activities. As most of methods for amide synthesis generate a large amount of waste
and suffer from low atom efficiency, a more environmentally friendly, safe and highly
atom-efficient method is still needed.
A palladium catalysed synthesis of amides from aromatic carboxylic acids and
isocyanates (RNCO) is investigated as an adaption of the CO2 ExIn (ExIn = Extrusion-
Insertion) reactions developed for the synthesis of thioamides from carboxylic acids
and isothiocyanates (RNCS).[1] Multistage mass spectrometry (MSn) experiments for
model systems established “proof of concept” demonstrating decarboxylation of
[(L)nPd(O2CAr)]+, to give [(L)nPdAr]+, followed by reaction with an isocyanate, to yield
[(L)Pd(NRC(O)Ar)]+. DFT calculations predicted these reactions to be highly
exothermic and occur via isocyanate insertion into the Pd-C bond.
The individual reaction steps associated with the conversion of 2,6-dimethoxybenzoic
acid into amides in solution was probed by 1H NMR spectroscopy as was the use of
stoichiometric amounts of Pd(O2CCF3)2 and isocyanates. The best identified reaction
conditions for this one-pot method gave moderate to high yields of amide depending
on the isocyanate employed.
A mechanistic understanding obtained from these model studies encouraged
development of a solution phase synthesis of amides using a catalytic amount of
palladium. Based upon previous work, a one-pot catalytic microwave protocol was
investigated in which palladium salts, ligands and solvent were screened. The use of
Pd(O2CCF3)2, 6-methyl-2,2’-bipyridyl and trifluoracetic acid (TFA) in N-methyl-
pyrrolidinone (NMP) provided the corresponding amides in 63-84% yields.
References
[1] A. Noor, J. Li, G. N. Khairallah, Z. Li, H. Ghari, A. J. Canty, A. Ariafard, P. S. Donnelly and R. A. J.
O’Hair,Chem. Commun., 2017, 53, 3854-3857.
Poster Presentations
96 12th Australasian Organometallics Meeting
Reductive Trimerization of CO to the Deltate Dianion using
Activated Magnesium(I) Compounds
K. Yuvaraj,† Iskander Douair,‡ Albert Paparo,† Laurent Maron,‡ Cameron Jones*,†
†School of Chemistry, Monash University, Melbourne, VIC, 3800, Australia
‡ Université de Toulouse et CNRS, INSA, UPS, F-31077 Toulouse, France
Carbon monoxide is a cheap and abundant industrial feedstock. In combination with
H2 (i.e. in synthesis gas: CO/H2) it is utilized as a versatile C1 building block in, for
example, the Fischer-Tropsch (F-T) process.[1] In order to model the fundamental
steps of the F-T process, recent interest has lain with the reductive homologation of
CO (possessing one of the strongest bonds known (BDE = 257 kcal/mol)[2]) with low-
valent organometallic compounds, yielding cyclic and acyclic oxocarbon anions, e.g.
ethynediolate [C2O2]2- and cyclic aromatics [CnOn]2- (n = 3-6), under mild conditions.
In this context, the first molecular Mg(I) complexes were synthesised in 2007, and have
been shown to be versatile reducing agents,[3] but they do not couple CO. 1:1 reactions
of magnesium(I) complexes with NHCs or DMAP (4-dimethylaminopyridine) yield
unsymmetrical magnesium(I)-adduct complexes, [(L)(D)Mg−Mg(L)] (L = -
diketiminate) which markedly increase the Mg−Mg bond distances of the systems.
Interestingly, two of these highly activated species are shown to reductively trimerize
CO to yield rare crystallographically characterised examples of the planar, aromatic
deltate dianion, incorporated in the complexes [{(L)(D)Mg}(-C3O3){Mg(L)}]2 (Scheme
1)[4].
Scheme 1. Synthesis of deltate complexes.
References
[1] a) A. Y. Khodakov, W. Chu, P. Fongarland, Chem. Rev. 2007, 107, 1692; b) C. K. Rofer-
DePoorter, Chem. Rev. 1981, 81, 447.
[2] R. Kalescky, E. Kraka, D. Cremer, J. Phys. Chem. A 2013, 117, 8981.
[3] a) S.P. Green, C. Jones, A. Stasch, Science 2007, 318, 1754.
[4] K. Yuvaraj, I. Douair, A. Paparo, L. Maron, C. Jones, 2019 (Manuscript submitted).
Poster Presentations
97 12th Australasian Organometallics Meeting
Towards High-Generation Ruthenium Alkynyl Dendrimers
for Nonlinear Optics
Ling Zhang, Mahbod Morshedi, Mark G. Humphrey*
Research School of Chemistry, Australian National University, Canberra ACT 2601,
Australia. E: [email protected]
Materials with nonlinear optical properties (NLO), especially multi-photon absorption
(MPA) properties are of significant interest for applications such as microfabrication,
bioimaging, photodynamic therapy, and frequency up-conversion lasing [1]. Studies
showed ruthenium alkynyl dendrimers demonstrated promising potential for MPA
properties [2-4]. A series of third-generation ruthenium alkynyl dendrimers and zero-,
first and second-generation homologues were synthesized. The size, purity, and
structural features of the dendrimers were assessed by a combination of 31P NMR
spectroscopy, diffusion-ordered spectroscopy (DOSY) [5], size-exclusion
chromatography (SEC), HR-ESI mass spectrometry, and transmission electron
microscopy (TEM).
Ruthenium alkynyl dendrimers of zero-, first-, second- and third-generations
References
[1] He, G. S.; Prasad, P. N., et al., Chem. Rev., 2008, 108, 1245-1330.
[2] Green K A, Humphrey, M. G., et al., Macromol. Rapid Comm., 2012, 33, 573-578.
[3] Simpson, P. V.; Humphrey, M. G. et al., Angew. Chem. Int. Ed., 2016, 55, 2387-2391.
[4] McDonagh, A. M.; Humphrey, M. G., et al., J. Am. Chem. Soc., 1999, 121, 1405-1406.
[5] Evans R, Morris G. A., et al. Angew. Chem. Int. Ed., 2013, 52, 3199-3202.
98 12th Australasian Organometallics Meeting
List of Attendees for the 12th Australasian Organometallics Meeting (OZOM12),
School of Chemistry, The University of Melbourne, 9th – 12th July 2019
First name Surname Institution
Aidan Matthews Monash University
Aidan McKay University of Otago
Alasdair McKay The University of Melbourne
Alexander Bissember University of Tasmania
Allan Canty University of Tasmania
Alphonsine Ngo Ndimba Australian National University
Angelo Frei The University of Queensland
Angus Shephard James Cook University
Angus Gillespie The University of Western Australia
Annie Colebatch University of Cambridge
Anthony Hill Australian National University
Asif Noor The University of Melbourne
Becky Fuller Curtin University
Benjamin Frogley Australian National University
Brendan Abrahams The University of Melbourne
Carol Hua The University of Melbourne
Cheesheng Onn Australian National University
Chiara Caporale Curtin University
Chuanzhu Gao Monash University
Colette Boskovic The University of Melbourne
Cory Smith Monash University
Curtis Ho University of Tasmania
Dafydd Jones Monash University
Daniel Harrison The University of Western Australia
Daniel Van Zeil Monash University
Daven Foster The University of Western Australia
David McMorran University of Otago
Declan Burke The University of Western Australia
Dr. Albert Paparo Monash University
Drasko Vidovic Monash University
Frank T. Edelmann Otto von Guericke University Magdeburg
Frederic PAUL Institut des Sciences Chimiques de Rennes
George Laffan Australian National University
George Koutsantonis The University of Western Australia
Glen Deacon Monash University
Guy Jameson The University of Melbourne
Harrison Barnett Australian National University
Howard Ma The University of Melbourne
Huan Wang Australian National University
99 12th Australasian Organometallics Meeting
Ian Rae The University of Melbourne
Isabelle Dixon Universite Toulouse III Paul Sabatier
James Findlay University of Otago
Jamie Hicks Australian National University
Jamie Greer Monash University
Jeremy Stone The University of Western Australia
Jian-Zhong Wu The University of Western Australia
Jun Du Australian National University
Kirralee Burke Monash University
Koushik Venkatesan Macquarie University
Lachlan Watson Australian National University
Lachlan Barwise La Trobe University
Lachlan Sharp-
Bucknall
La Trobe University
Lachlan McInnes The University of Melbourne
Liam Burt Australian National University
Liam Stephens Monash University
Ling Zhang Australian National University
Lou Rendina The University of Sydney
Lynn Lisboa University of Otago
Maggie Aulsebrook Australia’s Nuclear Science and Technology
Organisation (ANSTO)
Mahbod Morshedi Australian National University
Marcus Korb The University of Western Australia
Mark Humphrey Australian National University
Mark Rizzacasa The University of Melbourne
Masnun Naher The University of Western Australia
Matthew Gyton University of Warwick
Max Massi Curtin University
Max Roemer Macquarie University
Megan Herdman Monash University
Melissa Werrett Monash University
Michael Hall The University of Western Australia
Michael Stevens Monash University
Mohammad Al Bayer La Trobe University
Monica Perez-
Temprano
Institute of Chemical Research of Catalonia
Nicholas Tan Curtin University
Nick Cox Australian National University
Nigel Lucas University of Otago
Nilan Withanage La Trobe University
Nimrod Eren Monash University
100 12th Australasian Organometallics Meeting
Palak Garg Monash University
Parvin Safari The University of Western Australia
Paul Low The University of Western Australia
Paul Donnelly The University of Melbourne
Penelope Brothers Australian National University
Peter Junk James Cook University
Quinn van Hilst University of Otago
Rachel Steen University of York
Rebekah Duffin Monash University
Richard O'Hair The University of Melbourne
Richard Manzano Australian National University
Robert Malmberg Macquarie University
Ryan Huo Monash University
Samantha Orr Monash University
Sarmi Munuganti Monash University
Seyed
Mohammad
Bagher
Hosseini
Ghazvini
The University of Western Australia
Shazia Nawaz Monash University
Sigridur Suman University of Iceland
Sinead Keaveney Macquarie University
Sneha Mullassery Monash University
Stacey Rudd The University of Melbourne
Stephen Best The University of Melbourne
Steven Welsh Australian National University
Stuart Batten Monash University
Victoria Blair Monash University
Weam Altalhi The University of Melbourne
William Erb Université de Rennes 1
Yang Yang The University of Melbourne
Yong-Shen Han Australian National University
Yu Qing Tan Monash University
Yuvaraj Kuppusamy Monash University
Zhifang Guo Monash University
Zilin Wang The University of Melbourne