A Novel Approach to the Asymmetric Synthesis of Epoxides, Allylic Alcohols, α-Amino Ketones, and α-Amino Aldehydes from Carbonyl Compounds through α,β-Epoxy Sulfoxides Using the Optically Active p-Tolylsulfinyl Group To Induce Chirality

Article abstract of DOI:10.1021/jo00274a032

A practical and relatively inexpensive procedure for the preparation of (-)-chloromethyl p-tolyl sulfoxide of high optical purity was accomplished by the chlorination of optically pure (+)-methyl p-tolyl sulfoxide with N-chlorosuccinimide in the presence of K2CO3.The (-)-chloromethyl p-tolyl sulfoxide was alkylated to give a diastereomeric mixture of (-)-1-chloroalkyl p-tolyl sulfoxides.Addition of the anion derived from these sulfoxides to ketones or aldehydes afforded chlorohydrins in quite good yields with complete 1,2-asymmetric induction.Treatment of these chlorohydrins with a base gave optically active α,β-epoxy sulfoxides.On treatment with n-BuLi, the α,β-epoxy sulfoxides gave epoxides or allylic alcohols of high optical purity.This novel procedure was applied to a short synthesis of optically active (+)-disparlure, the sex attractant of the female gypsy moth.Aminolysis of the α,β-epoxy sulfoxides gave optically active α-amino ketones and α-amino aldehydes in quite good yields.