Hydrogen–deuterium exchange studies in the 1,3-elimination reactions of sulphoxides

Abstract

Deuterium exchange studies of the reactions of a series of 2-alkyl-1-methylsulphinyl-3-phenylpropanes to form trans-2-alkyl-1-phenylcyclopropanes in [²H₅]dimethylsulphinyl carbanion–[²H₆]dimethyl sulphoxide support a stepwise mechanism with the reversible formation of a carbanion in the first step. The mechanism of 1,3-elimination reactions is discussed and approximate rate constants have been assigned to each of the steps of the cyclisation reaction.