Palladium‐Catalyzed Cascade CH Trifluoroethylation of Aryl Iodides and Heck Reaction: Efficient Synthesis of ortho ‐Trifluoroethylstyrenes

A palladium‐catalyzed selective CH bond trifluoroethylation of aryl iodides has been explored. The reaction allows for the efficient synthesis of a variety of ortho ‐trifluoroethyl‐substituted styrenes. Preliminary mechanistic studies indicate that the reaction might involve a key Pd IV intermediate, which is generated through the rate‐determining oxidative addition of CF 3 CH 2 I to a palladacycle; the bulky nature of CF 3 CH 2 I influences the reactivity. Reductive elimination from the Pd IV complex then leads to the formation of the aryl–CH 2 CF 3 bond.