Efficient Desymmetrization of “<i>Pseudo</i>”-<i>C</i>₂-Symmetric Substrates:  Illustration in the Synthesis of a Disubstituted Butenolide from Arabitol

Abstract

A short synthesis of the homochiral disubstituted butenolide 1 is described in four steps from arabitol. The key steps are the selective kinetic protection of arabitol and the cyclization of 11 to form the butenolide ring. This last transformation represents a rare example of a fully stereoselective cyclitive desymmetrization process of a "pseudo"-C2-symmetric substrate.