CHIRAL RECOGNITION OF ALKYL 2-ARYLOXYPROPIONATES BY HPLC

Chiral resolution of a series of antiphlogistic methyl and ethyl 2-aryloxypropionates on R-DNBPG and S-DNBL analytical columns was attempted. Most of the resolved enantiomers were eluted in a very short time on both CSPs and the alpha and K' values of the chromatographic separations performed by R-DNBPG phase were generally better than those using S-DNBL. The elution order of the compounds was determined: the S isomer of all esters was eluted last from the R-DNBPG and viceversa from the S-DNBL column. The role of the substituents on the chiral resolution was also elucidated. It was hypothesized that the chiral interactions between the solutes and the CSPs were more influenced by the electronic features than by their steric hindrance. Finally, the chiral recognition mechanism which permitted resolution of the enantiomers was individuated.