Four kinds of secondary alcohols, 2-phenylcyclohexanol, 2-(4-trifluoromethylphenyl)-cyclohexanol, 2-(2-naphthalenyl)-cyclohexanol and 3-(1-hydroxyethyl)coumarin, were directly resolved on N- (3,5-dimethylphenyl)carbamate-substituted 6-O-β-cyclodextin bonded silica stationary phase by a normal- phase system with n-hexane-alcohol as a mobile phase. The influences of temperature, structure and concentration of the alcohol in the mobile phase on the separation of the four investigated solutes were investigated. It was found that the capacity factors for each diastereomer decreased either with increasing carbon number of alcohol or temperature while selectivity factor increased with temperature at the same molar concentration of alcohol, for which the reason was explained with a stoichiometric displacement model for retention and thermodynamic theory.

Key words: high performance liquid chromatography, derived β-cyclodextrin bonded stationary phase, enantioseparation, stoichiometric displacement model for retention, thermodynamics