Photoredox-Catalyzed Functionalization of Alkenes with Thiourea Dioxide: Construction of Alkyl Sulfones or Sulfonamides

摘要

Sulfonylation of alkenes through photoredox-catalyzed functionalization of alkenes with thiourea dioxide under visible-light irradiation is achieved.The reaction of alkenes,thiourea dioxide and electrophiles provides a green and efficient access to alkyl sulfones and sulfonamides.A broad reaction scope is presented with good functional group compatibility and excellent regioselectivity.A plausible mechanism involving a radical addition process with sulfur dioxide radical anion (SO2·-) derived from the oxidation of sulfur dioxide anion (SO22-) is proposed,which is supported by fluorescence quenching experiments.