CHROMATOGRAPHIC DETERMINATION OF ENANTIOMERIC PURITY BY ACHIRAL MEANS

A chromatographic method for determination of the enantiopurity of a chiral analyte using achiral reagents is described. The analyte is first converted to diastereomers utilizing either dimerization reactions of the analyte or a bifunctional (achiral) reagent. The diastereomers thus obtained constitute a meso compound and a dl pair, e.g. two epimeric pairs. The epimeric pairs are separated by HPLC on a C-18 (achiral) column. A mathematical equation was derived for determination of enantiomeric purity utilising the peak areas of the eluted epimers. This method takes into account differences in both reaction rates of the formation of the epimers and differences in their detector responses. The minimum amount of enantiomeric impurities (in the analytes studied) that could be detected by this method was approximately 0.002%.