Kinetic Resolution of Secondary 2‐Aryl‐1‐cycloalkanols with Phosphoroselenoyl Chloride with a Binaphthyl Group

Abstract

Phosphoroselenoic acid esters with a binaphthyl group were prepared by reacting phosphoroselenoyl chloride with excess racemic secondary cyclic alcohols. While the reactions of trans‐2‐aryl‐1‐cyclohexanols, 2‐pheny‐1‐cycloheptanols, and 2‐phenyl‐1‐cyclooctanols proceeded with high diastereoselectivity, those of 2‐alkyl‐1‐cylcohexanols and 2‐aryl‐1‐cyclopentanols did not show any diastereoselectivity. The resulting diastereomeric mixtures of the esters were purified by column chromatography on silica gel to give fractions that contained only one of the diastereomers. Reduction of the separated esters gave optically active cyclic alcohols with high enantiomeric excess. Extrusion of the selenium atom of the esters with PBu3 gave optically active phosphites in high yields.