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.

Keywords:

• Amides
• chiral molecular tools
• esters
• phosphoroselenoyl chlorides

Acknowledgments

This work was supported in part by Grant-in-Aid for Scientific Research on Priority Area (No. 19027021, “Synergy of Elements”) from the Ministry of Education, Culture, Sports, Science and Technology, Japan.