The chlorination of sulfides: A reassessment of product controlling factors

Abstract

A reexamination of previous proposais for the prediction of regioselectivity in sulfide chlorinations has found them to be unsatisfactory. A new basis for such predictions is advanced viz. the electronegativity difference (ΔX p ) of the substituents attached to the α- and α′-carbon atoms of the sulfide substrate. Upon establishing that the new basis for these predictions is satisfactory, it is successfully applied to the problem of predicting reactivity differences in isomeric sulfide chlorinations. The formation of isomeric sulfonium ions is used to establish the failure of possible isomerization processes to occur under normal reaction conditions.