Recent advances in aryl–aryl bond formation by direct arylation

The abundance of the biaryl structural motif in natural products, in biologically active molecules and in materials chemistry has positioned aryl-aryl (Ar-Ar) bond formation high on the agenda of synthetic chemists. For decades well-known reactions such as the Mizoroki-Heck and Suzuki-Miyaura have been the methods of choice to furnish biaryls. More recently, however, alternative methods, most notably direct arylation via C-H activation, have become the focus of many research groups. Compared to traditional methods, direct arylation affords Ar-Ar compounds in fewer steps by removing the need for prefunctionalisation. Furthermore, given that either one or two hydrogens are targeted, less waste and good atom…