C-H Functionalization of Biaryl Compounds

In recent years, C-C, C-N, and C-O bonds constructed by C-H functionalization have reached considerable attention due to excellent functional group tolerance, cost-effectiveness, and atom-economy. Biaryl compounds are one of the important skeletons in the field of organic chemistry, and have been extensively applied to pharmaceuticals, functional materials, and agrochemicals. However, there have been far fewer reports on C-H functionalization by employing biaryls as substrates. Herein we comprehensively review the C-H functionalization of biaryls including annulation/substitution reactions. The discussion is subdivided according to specific reaction types. In summary, we analyzed the corresponding reaction from the points of view of conditions, directing groups, mechanism, and applications. We hope that this minireview will be beneficial for more synthetic chemists to grasp the design of C-H functionalization of biaryl compounds and enlighten them with more ideas on this issue.