Catalytic Decarboxylative Radical Sulfonylation

Sulfones are key structural motifs in pharmaceuticals and agrochemicals, and their synthesis is of paramount importance in organic chemistry. While nucleophilic and electrophilic C(sp(3))-sulfonylation are well documented, radical C(sp(3))-sulfonylation remains elusive. Herein, we report the decarboxylative radical sulfonylation with sulfinates. With the merger of 4CzIPN (1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene) and Cu(OTf)(2) as catalysts, the visible-light-induced reaction of redox-active esters of aliphatic carboxylic acids with organosulfinates at room temperature provides the corresponding decarboxylative sulfonylation products in satisfactory yields. This redox-neutral protocol exhibits broad substrate scope and wide functional group compatibility, enabling the late-stage modification of complex natural products and bioactive pharmaceuticals. The synthetic utility of the method is further demonstrated by the improved synthesis of anti-prostate cancer drug bicalutamide. A mechanism involving sulfonyl group transfer from Cu(II)-SO2R to alkyl radicals is proposed.