Synthesis and thermolysis of 2-(phenylthio)ethanesulfonyl chloride. The absence of a reported "rearrangement of radicals with migration of the chlorine atom from sulfur to carbon"

Abstract

2-(Phenylthio)ethanesulfonyl chloride (1) is the major product of the reaction of (a) lithium 2-(phenylthio)ethanesulfinate (6) and chlorine, and, notwithstanding contrary reports, also of (b) benzenethiol (3) and ethenesulfonyl chloride (4), and (c) sodium 2-(phenylthio)ethanesulfonate (5) and phosphorus pentachloride. The rearrangement referred to in the title, which was proposed to account for the isolation of 2-(phenylthio)ethyl chloride (2) rather than 1 from 3 and 4, therefore does not occur. Desulfonylation of 1 to form 2, however, readily takes place thermally and, in accord with a rate-determining internal displacement of the chlorosulfonyl group with formation of the episulfonium ion, shows a substantial increase in rate with increase in solvent polarity.