Nickel-catalyzed direct coupling of heteroarenes

Nickel-catalyzed cross-coupling reactions have recently been receiving significant attention from the synthetic community as a way to construct carbon-carbon or carbon-heteroatom bonds, because nickel catalysts are less expensive and less toxic than palladium catalysts. We herein describe our recent developments in nickel-catalyzed biaryl coupling methodology, along with mechanistic studies and applications to the synthesis of natural products and pharmaceuticals. In particular, we focus on nickel-catalyzed direct coupling reactions in which "unreactive" bonds such as C-H, C-O, and C-C bonds are converted into biaryl moieties.