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The Chemical Educator
ISSN: 1430-4171 (electronic version)
Abstract Volume 20
(2015) pp 265-267
An Improved Resolution of (±)-1-Phenylethylamine
Daniel D. Clark,* Peter D. McFadden, and Emily S. Wilson
Department of Chemistry, Mathematics, and Physics, Clarion University of Pennsylvania, 840 Wood Street, Clarion, PA 16214, dclark@clarion.edu
Received August 26, 2015. Accepted October 6, 2015.
Published: 9 October 2015
Abstract. Stereochemistry and polarimetry are often introduced in organic chemistry laboratory with the resolution of (±)-1-phenylethylamine using (+)-tartaric acid as the resolving agent. However, there are significant drawbacks to the commonly used experimental procedure. Isolating the resolved (–)-1-phenylethylamine from solution is problematic as it is viscous, reacts with the atmospheric carbon dioxide, and stinks. Furthermore, the use of a full equivalent of (+)-tartaric acid resolving agent requires a large volume of solvent. We have developed two practical improvements to this experiment: (1) By keeping the resolved amine in solution and measuring its concentration with refractometry, the isolation of the problematic neat amine is avoided; and (2) By decreasing the amount of resolving agent, the resolution can be accomplished using appreciably less solvent and generating less chemical waste, thus making the experiment greener.
Key Words: Laboratories and Demonstrations; organic chemistry; stereochemistry; optical resolution; experiment; optical purity
(*) Corresponding author. (E-mail: dclark@clarion.edu)
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Supporting Materials:
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