Influence of the kind of the alcoholic modifier on chiral separation on a Chiralpak AD column

The enantioselective separation of substituted 3-phenoxy-1,2-propanediols (PPDs) and aziridinecarboxylic acid derivatives (ACAs) on Chiralpak AD, an amylose-based chiral stationary phase, was investigated. All solutes could be separated using hexane-alcohol mobile phases. The retention times for sixteen out of seventeen substituted PPDs and from all the ACAs increased on changing the alcoholic modifier from 2-propanol to ethanol or ethanol-methanol mixtures. The separation factors of sixteen out of seventeen PPDs and nine out of twelve ACAs were improved using ethanol or ethanol-methanol mixtures instead of 2-propanol.