28. Stereochemical Nomenclature; Racemization and Resolution

Freshman Organic Chemistry (CHEM 125)

Determination of the actual atomic arrangement in tartaric acid in 1949 motivated a change in stereochemical nomenclature from Fischer's 1891 genealogical convention (D, L) to the CIP scheme (R, S) based on conventional group priorities. Configurational isomers can be interconverted by racemization and epimerization. Pure enantiomers can be separated from racemic mixtures by resolution schemes based on selective crystallization of conglomerates or temporary formation of diastereomers.

00:00 - Chapter 1. Ambiguity in the D/L Genealogical Designations
10:15 - Chapter 2. The Discovery of Tartaric Acid's Atomic Arrangement and Notation by Priority
24:49 - Chapter 3. The Cahn-Ingold-Prelog Priority Scheme
34:12 - Chapter 4. Racemization and Epimerization

Complete course materials are available at the Open Yale Courses website: http://open.yale.edu/courses

This course was recorded in Fall 2008.