Enantiomer Self-Disproportionation of Chiral Compounds on Achiral Ordered Mesoporous Silica M41S and Regular Silica Gel as a Stationary Phase

Chromatographic behavior of nonracemic mixtures, viz., mandelic acid and stilbene oxide as analytes has been studied in detailed by enantiomer self-disproportionation on achiral ordered inesoporous material M41S and regular silica gel as stationaty phases. Enantiomer self-disproportionation gave enhanced separation of analytes. The extent and magnitude of enantiomer self-disproportionation is dependent. on the optical purity of the starting non-racemic molecules, presence of intermolecular hydrogen bonding/pi-pi interactions and the nature of eluents used. The present Study and previous literature data suggest that percentage ee of a nonracemic mixture needs to be determined before any chromatographic purification is taken Lip as enantiomer self-disproportionation phenomenon could occur during purification. The data show [bat enantiomer self-disproportionation of nonracemic mixtures can be harnessed for its enantioenrichment on inexpensive achiral stationary phases. Chirality 21:255-261, 2009. (C) 2008 Wiley-Liss, Inc.