Liquid Chromatographic Resolution of 1,1′‐Bi‐2‐Naphthol and 3,3′‐Diaryl‐1,1′‐bi‐2‐Naphthols on Pirkle‐Type Chiral Stationary Phases Based on Leucine and Phenylglycine

Abstract

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‐1,1′‐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 1,1′‐bi‐2‐naphthol on the CSPs based on (S)‐N‐(3,5‐dinitrobenzoyl)leucine N‐propylamide and (S)‐N‐(3,5‐dinitrobenzoyl)phenylglycine N‐propylamide were opposite to those for the resolution of 3,3′‐diaryl‐1,1′‐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.

Keywords:

• Enantiomer separation
• chiral stationary phase
• 1,1′‐bi‐2‐naphthol
• 3,3′‐diaryl‐1,1′‐bi‐2‐naphthols

Acknowledgment

This work has been supported by a grant from KISTEP (NRL Program: M1‐0318‐00‐0005).