First highly asymmetric Pummerer-type reaction in chiral, non-racemic acyclic sulfoxides induced by O-silylated ketene acetal

Abstract

Various types of syn- and anti-β-substituted sulfoxides 6b–e, g reacted with ketene tert-butyldimethylsilyl acetal 2 in the presence of a catalytic amount of zinc iodide in acetonitrile to give high yields of the corresponding α-siloxy sulfides 7b–e, g stereoselectively. Similarly, chiral, nonracemic sulfoxides 6a, f, h, i reacted with acetal 2 in acetonitrile to give the chiral, non-racemic α-siloxy sulfides 7a, f, h, i in high yields.