Cu(OTf)2-mediated C(sp2)-H arylsulfonylation of enamides via the insertion of sulfur dioxide

An efficient and straightforward 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 has been developed. This Cu(OTf)(2)-mediated SO2 insertion reaction proceeds smoothly to afford a diverse range of -amidovinyl sulfones bearing manifold functional groups in moderate to excellent yields with high regio- and stereoselectivities.