Nickel-Catalyzed Methylation of Aryl Halides with Deuterated Methyl Iodide

A nickel-catalyzed methylation of aryl halides with cheap and readily available CH3I or CD (3) I is described. The reaction is applicable to a wide range of substrates and allows installation of a CD3 group under mild reaction conditions without deuterium scrambling to other carbon atoms. Initial mechanistic studies on the stoichiometric and catalytic reactions of the isolated [(dppp)Ni(C6H4-4-CO2Et)Br] [dppp= 1,3-bis(diphenylphosphanyl)propane] suggest that a Ni-0/ Ni-II catalytic cycle is favored.