Liquid Chromatographic Resolution of l,l;-Bi-2-Naphthol and S^'-Diaryl-M'-bkZ-Naphthols on Pirkle-Type Chiral Stationary Phases Based on Leucine and Phenylglycine

摘要

Pirkle-type chiral stationary phases (CSPs) based on (S)-leucine and (S)-phenylglycine were applied in the resolution of 1,1'-bi-2-naphthol and 3,3'-diaryl-l'-bi-2-naphthols. Among the two Pirkle-type CSPs, the one based on (S)-N-(3,5-dinitrobenzoyl)leucine N-propylamide was found to be excellent and most widely applicable. Interestingly, the elution orders for the resolution of l,l'-bi-2-naphthol on the CSPs based on (S)-.N-(3,5-dinitrobenzoyl)leucine N-propylamide and (S)-N-(3,5-dinitrobenzoyl)phenylglycine Af-propylamide were opposite to those for the resolution of 3,3'-diaryl-l,l'-bi-2-naphthols. In order to rationalize the reversed elution orders, we proposed two different chiral recognition mechanisms based on the chromatographic resolution behaviors, with the aid of the CPK molecular model study.