Direct C(sp2)-H Arylsulfonylation of Enamides via Iridium(III)-Catalyzed Insertion of Sulfur Dioxide with Aryldiazonium Tetrafluoroborates

An iridium(III)-catalyzed three-component reaction of enamides, aryldiazonium tetrafluoroborates, and 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) (DABSO) for the direct C(sp(2))-H arylsulfonylation of enamides is developed. This transformation provides a robust and straightforward approach for preparing a diverse array of beta-amidovinyl sulfones in moderate to excellent yields and high stereoselectivities without Light-emitting diode (LED) radiation. This transformation also features mild conditions, broad substrate scopes, and excellent functional group tolerance.