A Well-Defined, Air-Stable NHC-Ni Precatalyst for C-N Bond Formation.

A new, well-defined, air-stable N-heterocyclic carbene nickel(II) precatalyst [(IPr)Ni(N-methylphenethylamine)Cl] (IPr = N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) was designed, synthesized, and evaluated for C-N cross-coupling reactions. This precatalyst is readily activated in the presence of base and efficiently promotes the amination of a variety of aryl chlorides with amines. Optimization studies established robust reaction conditions and revealed the influence of electronic and steric properties of the coupling partners on catalytic performance. The combination of operational simplicity, long-term bench stability, and facile activation makes this NHC-Ni precatalyst a good choice for nickel-catalyzed C-N bond formation.