Synthesis and structure of aliphatic phenylchloronium ylide

Aliphatic phenylchloronium ylide with bis(trifluoromethylsulfonyl)‐methylidene group was synthesized. Thermal transylidation of 4‐(trifluoromethyl)phenylbromonium bis(trifluoromethylsulfonyl)methylide in chlorobenzene as a solvent at 130°C afforded phenylchloronium bis(trifluoromethylsulfonyl)methylide in a moderate yield. Phenylbromonium and phenyliodonium ylides were also prepared by the thermal transylidation to bromo‐ and iodobenzenes. The reaction probably involves initial thermal generation of bissulfonylcarbene (Tf 2 C:), followed by nucleophilic attack of a halobenzene toward the electron‐deficient carbene center. Solid‐state structures of these aliphatic phenylhalonium ylides were analyzed and compared with each other.