Self-disproportionation of enantiomers of isopropyl 3,3,3-(trifluoro)lactate via sublimation: Sublimation rates vs. enantiomeric composition

The presented results convincingly demonstrate that self-disproportionation of enantiomers via sublimation is substantially more complex phenomenon then was previously believed. We demonstrate that the racemic form of isopropyl 3,3,3-trifluoro-2-hydroxypropanoate (1) sublimed faster regardless of the starting enantiomeric composition of the enantiomerically enriched mixtures studied in the range from 20.8, 36.8, 58.7 to 79.4% ee. This preferential sublimation of the racemic form allowed for, the most possibly simple, preparation of optically pure samples of compound 1. In this work we also suggest some general experimental procedures, which may be easily used to facilitate the interpretation of the data collected in different laboratories. (C) 2009 Elsevier B.V. All rights reserved.