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Transition to an Investigative Laboratory Program in
Chemistry at Birmingham-Southern College
David J. A. Schedler and
Laura K. Stultz
Introduction
• National Science Foundation Grant
• Investigative Laboratories
• Development of Laboratory Projects
• Examples
Project Goals
Student Goals
Improve
- Problem solving and collaborative skills
- Ability to apply experimental techniques to solve a chemical problem.
- Ability to communicate results (written and oral)
Curricular Goals
- Improved laboratory experience
- Better synergy between lecture and laboratory
- Connections between chemistry courses
Investigative Laboratories
• Students discover results instead of verifying them
• Experimental protocols are largely student designed
• Work is done in collaborative groups• Interpretation of results through data
analysis• Group discussion
Project Plan
Gradualism Model – stepwise presentation of new material with specific goals
Instrumental techniques as common thread
- Molecular Modeling
- FTNMR (1H and 13C)
Project based Laboratories – Reinforces concepts and skills
Student involvement in laboratory design
• First Semester Focuses on Techniques and Instrumentation• Distillation
• Crystallization
• Melting point
• TLC
• GC
• NMR
• Second Semester Focuses on Application• NMR
• FT-IR
• Molecular modeling
• Stereochemistry and Coupling Constants
• Projects should have clearly stated:• Objective• Outcome• Introduction
• Theory for the instrumentation to be used
• background into the chemistry involved
• Experimental Procedure
1.34 kcal/mol2.39 kcal/mol
trans-3-methylcyclohexan-1-ol
NaOH, H2O
NaBH4
H3C
O
H3C
OH
cis-3-methylcyclohexan-1-ol
H3C
OH
Hax
OH
H3C
Heq
Hax
Heq
Heq
HaxH3C
OH
Hax
Hax
Heq
Heq
Entry Dihedral ExpectedDihedral
Angle (°)
Expected value
(Hz)
1 HaxCCHeq 60 2.5
2 HaxCCHeq 60 2.5
3 HaxCCHax 180 12
4 HaxCCHax 180 12
Entry Dihedral ExpectedDihedral
Angle(°)
Expected value
(Hz)
1 HeqCCHeq 60 2.5
2 HeqCCHeq 60 2.5
3 HeqCCHax 60 2.5
4 HeqCCHax 60 2.5
OH
Heq
Heq
Hax
Hax
OH
Heq
Hax
Hax
Jax-ax
Jax-eq
Heq
Jax-eq
H3C
OH
H
Hax
Jax-ax
Jax-eq
Heq
Jax-eq
Ψ Quintet Ψ Triplet of Ψ triplets
Diels-Alder Reaction• prediction of reaction
product
• carry out reaction using previously learned lab techniques
CH3
OH
+ O
O
O
toluene
CH3
OH
O
O
O
Adapted from: McDaniel, Keith F.; Weekley, R. Matthew “The Diels-Alder Reaction of 2,4-Hexadien-1-ol
with Maleic Anhydride: A Novel Preparation for the Undergraduate Organic Chemistry Laboratory Course” J. Chem. Educ. 1997, 74, 1465.
Structure Determination
•NMR
•IR
•Mechanistic explanation
CH3
OH
O
O
O CH3
O
OH
O
O
CH3
O
OH
O
OH1
H2
H3H4
A
Dihedral MeasuredAngle A(°)
CalculatedJ Value A(Hz)
MeasuredAngle B(°)
CalculatedJ Value B(Hz)
H1CCH2 18.93 8.42 179.31 11.19
H2CCH3 40.36 5.61 53.33 3.64
H3CCH4 45.28 4.85 99.05 1.18
CH3
O
OH
O
OH1
H2
H3H4
B
www.casper.organ.su.se/ke3690/jhh.htmlprogram calculates 3JHH values according to:
C.A.G. Haasnoot, F.A.A.M. DeLeeuw and C. Altona Tetrahedron 36 (1980) 2783-2792
CH3
O
OH
O
OH1
H2
H3H4
CH3
O
OH
O
OH1
H2
H3H4
A
H2
H3
H1
Dihedral MeasuredAngle
(°)
CalculatedJ Value A
(Hz)
MeasureJ Value A
(Hz)
H1CCH2 18.93 8.42 8.9
H2CCH3 40.36 5.61 5.5
H3CCH4 45.28 4.85 4.6
• Electron Transfer Self Exchange Rates• Kinetic NMR
experiment
• Factors that affect the electron transfer rates
FeII FeIII
+
+ FeIII
+
FeII+
Jameson, D.L.; Anand, R. J. Chem. Ed., 2000, 77, 88
Acknowledgements
• National Science Foundation
(Award DUE-0126478)
• Dr. Regina Stanton
• Mr. Patrick McTamney
• Ms. Karen Johnson
• Mr. Nathan Boyd
• Birmingham-Southern College
• www.bsc.edu/chemistrylabs.htm
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