Temperature Controlled Selective C-S or C-C Bond Formation: Photocatalytic Sulfonylation versus Arylation of Unactivated Heterocycles Utilizing Aryl Sulfonyl Chlorides.

A visible-light-induced photocatalytic method for the arylsulfonylation of heterocycles has been developed. The synthetic utility of this reaction is reflected by the direct use of commercially available sulfonyl chlorides and heterocycles under room temperature conditions. Complementarily, the photocatalytic arylation of heterocycles by sulfonyl chlorides via extrusion of SO2 is feasible at elevated temperature conditions, allowing switching between arylation or arylsulfonylation with excellent chemoselectivity.