Phosphoroselenoic Acid Derivatives Bearing a Binaphthyl Group as a Chiral Molecular Tool

Abstract

New synthetic methods for phosphoroselenoic acid derivatives bearing 1,1′-bi-2-naphthyl group and their use as new chiral molecular tools have been described. Phosphoroselenoyl chloride is prepared in high yields from PCl 3 , elemental selenium, and 1,1′-bi-2-naphthol. The conversion of the chloride to esters and amides are readily achieved by reacting with the corresponding alcohols and amines as electrophiles. The esters are obtained as a diastereomeric mixture in a ratio of almost 1:1. In 31 P and 77 Se NMR spectra, the diastereomers are discriminated even when two similar types of substituents are attached to the chiral carbon atom of the alcohols. The treatment of the amides with PBu 3 leads to phosphoramidites. The addition of H 2 O to the chloride in the presence of Et 3 N gives the phosphoroselenoic acid salt with high efficiency.