Sodium halide-switchable divergent electrochemical synthesis of sulfonyl chlorides and thiosulfonates from thiols

Abstract

A salt-controllable electrochemical methodology for the synthesis of sulfonyl chlorides and thiosulfonates from thiol precursors has been developed, commencing with a good range of thiols and utilizing readily available sodium chloride and sodium bromide, which, in addition to acting as suitable electrolytes, are bifunctional, serving simultaneously as both catalysts and reagents in the reaction. A key finding is the halide-dependent control of product selectivity. The electrochemical synthesis affords the sulfonyl chloride when conducted in the presence of NaCl. Substituting the halide source with NaBr redirects the reaction pathway, yielding the thiosulfonate as the predominant product. The syntheses are conducted under mild and environmentally benign electrochemical conditions under constant current within a user-friendly undivided cell arrangement.