INVESTIGATION OF THE ENANTIOSELECTIVE SEPARATIONS OF ALPHA-ALKYLARYLCARBOXYLIC ACIDS ON AN AMYLOSE TRIS(3,5-DIMETHYLPHENYLCARBAMATE) CHIRALSTATIONARY-PHASE USING QUANTITATIVE STRUCTURE-ENANTIOSELECTIVE RETENTION RELATIONSHIPS - IDENTIFICATION OF A CONFORMATIONALLY DRIVEN CHIRALRECOGNITION MECHANISM

A series of 28 chiral alpha-alkyl arylcarboxylic acids were chromatogr aphed on an amylose tris(3,5-dimethylphenylcarbamate) chiral stationar y phase (AD-CSP). The retention data were correlated to a series of mo lecular descriptors to produce quantitative structure-enantioselective retention relationships (QSERR) incorporating the hydrogen bonding ab ility and aromaticity of the solutes. The QSERR equations were used to guide molecular modelling experiments designed to investigate the chi ral recognition mechanism responsible for the observed enantioselectiv e separations. The results of the study indicate that unlike the stand ard ''three-point interaction'' model of chiral recognition, enantiose lectivity was due to a ''conformationally driven'' chiral recognition process.