α,β-Epoxy Sulfoxides as Useful Intermediates in Organic Synthesis. IX. A Novel Synthesis of Alkyl Vinyl Ketones and Divinyl Ketones from Carbonyl Compounds and 1-Chloro-3-phenylthiopropyl Phenyl Sulfoxide as a Three-Carbon Homologating Agent

Abstract

Abstract The α,β-epoxy sulfoxides easily derived from carbonyl compounds and 1-chloro-3-phenylthiopropyl phenyl sulfoxide were treated with sodium benzeneselenolate to give β-phenylthio carbonyl compounds in excellent yields. The phenylthio group was oxidized to the sulfinyl group and was then treated with a base to afford alkyl vinyl ketones in quite good yields. This reaction presents a novel method for the preparation of alkyl vinyl ketones from carbonyl compounds by three-carbon homologation. The treatment of α,β-epoxy sulfoxides mentioned above with benzenethiolate gave α,β′-bis(phenylthio) ketones. The elimination of the both thio groups afforded divinyl ketones.