Recent progress in nickel-catalyzed biaryl coupling

Nickel catalysis for biaryl coupling reactions has received significant attention as a less expensive and less toxic alternative to "standard" palladium catalysis. Here we describe recent developments in nickel-catalyzed biaryl coupling methodology, along with mechanistic studies and applications. In particular we focus on nickel-catalyzed coupling reactions in which "unreactive" bonds such as C-H, C-O, and C-C bonds are converted into biaryl moieties. Biaryl coupling through nickel catalysis has been known for a few decades. The topic has recently resurfaced in synthetic chemistry, however, thanks to its use of ideal coupling partners such as simple arenes (Ar-H) and phenol derivatives (Ar-OR). In this microreview, recent achievements in nickel-catalyzed biaryl coupling are summarized.