NHC-Nickel Catalyzed C-N Bond Cleavage of Mono-protected Anilines for C-C Cross-Coupling

A Ni-catalyzed aryl C-N bond cleavage of monoprotected anilines, N-arylsulfonamides, has been developed. A new N-heterocyclic carbene derived from benzoimidazole shows high reactivity for the C-N cleavage/C-C cross-coupling reaction. The ortho-directing group is not required to break the C-N bond of sulfonyl-protected anilines, which are not limited to p-extended anilines. The mechanistic studies have revealed that a sulfamidomagnesium salt is the key coupling intermediate.