Efficient C-N and C-S Bond Formation Using the Highly Active [Ni(allyl)Cl(IPr*OMe)] Precatalyst

Two new [Ni(allyl)Cl(NHC)] complexes with the bulky yet flexible N-heterocyclic carbene (NHC) ligands IPr* {N,N-bis[2,6-bis(diphenylmethyl)-4-methylphenyl]imidazole-2-ylidene} and IPr*(OMe) {N,N-bis[2,6-bis(diphenylmethyl)-4-methoxyphenyl]imidazol-2-ylidene} are reported. These complexes were employed in the amination and sulfination of aryl halide species and were shown to perform well in these reactions, which typically required less than half as much catalyst as previous state-of-the-art nickel complexes.