Fluoroalkanesulfinate Salts as Dual Fluoroalkyl and SO₂ Sources: Atom-Economical Fluoroalkyl-Sulfonylation of Alkenes and Alkynes by Photoredox Catalysis

We disclose that fluoroalkanesulfinate salts ((R_FSO₂)_nM) such as the Langlois reagent, CF₃SO₂Na, serve as dual fluoroalkyl (R_F) and sulfur dioxide (SO₂) sources by the action of photoredox catalysis. An operationally simple strategy for the vicinal installation of R_F and SO₂ groups onto unsaturated carbon–carbon bonds, i.e., fluoroalkyl-sulfonylation, has been developed. In particular, the present photocatalytic trifluoromethyl-sulfonylation can be applied to aromatic alkynes in addition to aliphatic and aromatic alkenes bearing various functional groups.