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