Controllable Double Difluoromethylene Insertions into S−Cu Bonds: (Arylthio)tetrafluoroethylation of Aryl Iodides with TMSCF₂Br

A new method of constructing “ArSCF 2 CF 2 Cu” from ArSCu and TMSCF 2 Br (TMS=trimethylsilyl) has been developed. The cross‐coupling reactions of the obtained “ArSCF 2 CF 2 Cu” with diverse aryl iodides (Ar′I) provide an efficient access to Ar′CF 2 CF 2 SAr. Mechanistic studies demonstrate that the “ArSCF 2 CF 2 Cu” species were generated through controllable double difluoromethylene insertions into ArS−Cu bonds rather than the 1,2‐addition of ArSCu to tetrafluoroethylene.