Metal-free visible-light-induced oxidative cyclization reaction of 1,6-enynes and arylsulfinic acids leading to sulfonylated benzofurans

A new and convenient visible-light-induced method has been developed for the synthesis of sulfonylated benzofurans via oxidative cyclization reaction of 1,6-enynes and arylsulfinic acids. This reaction was carried out under metal-free and mild conditions, in which the C–S, C-C and C = O bonds could be sequentially formed in one pot operation.