Green Chemistry in the Organic
Laboratory: A Beginning
A Brief History
ACS Meeting: San Diego, 2001
Green Chemistry Workshop: University of
Oregon, summer 2002
Green organic laboratory development: spring
and summer 2003; fall 2003 to present
A pilot program: fall and spring 2003-04
Green chemistry for all organic laboratory
sections: fall and spring 2004-05
Gary O. Spessard
Department of Chemistry
St. Olaf College
Northfield, MN 55057
(spessard@stolaf.edu)
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Epoxidation using OXONE
Experiments—First semester
Organic phase(ethyl acetate)H2OPhCH2OHPhCH2OHOHHCCH3H3COOH3CCCH3OCCH3H3COOH3CCCH3OKHSO5KHSO41) Hashimo
Recrystallization of an unknown
Synthesis of phenacetin—H2O as solvent
Conformational analysis using CAChe
Bromohydrin reaction using NBS—H2O as solvent
Hydroboration
Resolution of phenylsuccinic acid using L-proline
Acetylation of ferrocene—no solvent
Epoxidation of trans-cinnamyl alcohol
Diels-Alder reaction in an ionic liquid
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Diels-Alder Reaction in an Ionic
Liquid
Epoxidation and Diels-Alder
Reactions: The “Old” Way
H3CH3C+OOOH3CH3COHHOO50-60oIonic liquidHONCH3CH3CH3Cl-ZnCl2(1 : 2)
+ClCOOHOCH2Cl2/25oOClCOHO+SOOXylenes/130oOOO+OOOHH!+ SO2
Abbott, A. P.; Capper, G.; Davies, D. L.; Rasheed, R. K.;
Tambyrajah, V. Green Chemistry, 2002, 4, 24.
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Experiments—second semester
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Iodination of Anisole
Electrophilic iodination of anisole
Phenylpropanols from styrene oxide using a
Grignard reagent
N,N-Diethyl-m-toluamide
Ethyl (E,E)-5-phenyl-2,4-pentadienoate
Menthol to menthone using KMnO4—no solvent
Mixed aldol condensations: chalcones—no solvent
Reactions of salicylaldehyde—alkylation vs. aldol
condensation
Kinetic vs. thermodynamic control: synthesis of !and "-D-glucopyranose pentaacetate
OCH3KIO3/KI/HClMeOH/H2O/25o/20 hOCH3IAdimurthy,
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S; Ramachandriah, G.; Ghosh, P.K.; Bedekar, A
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What does green chemistry look
like?
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Future Objectives
Complete implementation of green chemistry
in organic laboratory courses
Develop green experiments for first-year
chemistry
Atom economy in the context of stoichiometry
Develop green chemistry experiments for
analytical laboratory courses
Improve classical procedures
Develop “real-time” analyses in conjunction with
organic laboratories
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What do the students say?
Acknowledgements
Students
“I don’t quite understand why one
would use such hazardous reagents and
solvents when the same experiment
could be done in less harsh conditions. I
really enjoyed paying attention to such
details.”
“…. it seems very smart to be practicing
green chemistry. I think all the
[chemistry] labs should be taught that
way.”
Kathy Van Heuvelen
Matt Patterson
All of our organic chemistry laboratory
students
Faculty
Bob Hanson
Paul Jackson
Financial support
W. M. Keck Foundation
Pfizer Corporation
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