Base‐free Suzuki‐Miyaura Coupling of ( Z )‐Trifluoromethyl Alkenyltriflates: An Efficient Approach to α ‐Trifluoromethyl Arylenes

An exogenous base is generally necessary for the traditional palladium‐catalyzed Suzuki‐Miyaura coupling reactions. We report a direct palladium‐catalyzed base‐free Suzuki‐Miyaura coupling reaction of α ‐trifluoromethyl alkenyl triflates and aryl boric acids. Using Pd(OAc) 2 (10 mol %) and PPh 3 (40 mol %) as catalyst, this reaction proceeds smoothly without base or other additive. A variety of common functional groups, such as methyl, phenyl, naphthyl, fluoride, chloride, bromide, cyano, thienyl and alkyl, were well tolerated and a series of α ‐trifluoromethyl arylenes were obtained in 84 %–100 % yields.