Visible-light photoredox-catalyzed aryl radical in situ SO2-capture reactions

Abstract

An aryl radical in situ SO₂-capture reaction is reported for the first time. Using aryl diazonium salts as arylradical precursors, and vinyl triflates and allyl(alkynyl) trifluoromethylsulfones as radical acceptors and in situ SO₂ donors, this protocol produces various β-keto, allyl and alkynyl arylsulfone derivatives, which are recognized as useful synthons. The reaction can be performed under mild visible-light photoredox-catalytic conditions without any external SO₂ sources.