Coupling between radical and anion in the outersphere oxidation of α-sulfonyl carbanions. Its role on the product distribution between dimeric olefins and disulfone

Article abstract of DOI:10.1016/S0040-4020(01)87067-8

The electrochemical oxidation of α-sulfonyl carbanions is shown to involve a coupling reaction between the electrogenerated radical and the parent anionic species, both on preparative and kinetic grounds. Two routes compete for the further evolution of the ensuing anion radical: (i) a two step desulfonylation leading to the dimeric olefin, the product of an overall catalytic process, (ii) or further oxidation leading to the dimeric disulfone. Relevance of this mechanism to transition metal oxidations of α-sulfonyl carbanions is examined.