Visible-Light-Driven Copper-Catalyzed Synthesis of Sulfonamides from Aryl-N₂BF₄ through One-pot Tricomponent Reaction

A method for preparing sulfonamides using visible light is described. In this approach, an aryl diazo tetrafluoroborate salt, 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) (DABSO), and amino benzoate as substrates, CuBr₂ as a catalyst, and 3-methyl-3-pentanol as an additive were employed for a one-pot multicomponent reaction to provide sulfonamides under mild reaction conditions. A variety of aryl diazo tetrafluoroborate salts and O-benzoyl hydroxylamines were tolerated in this process to provide products with yields up to 96%. (Figure presented.).