Direct C-H Functionalization of Heteroarenes via Redox-Neutral Radical Process: A Facile Route to C-C Bonds Formation

Aromatic heterocycles are an important class of compounds found in a wide range of natural products, pharmaceutically active molecules and organic materials. Recently, the direct radical functionalization of heteroaromatic C-H bonds has become an efficient and attractive method to access substituted heteroarenes. Especially, redoxneutral radical reactions have attracted much attention of chemists due to their potential advantages such as mild conditions, free of external oxidants, and good functional group tolerance. So far, a series of redoxneutral radical reactions have been developed. In this review, we mainly focus on the recent advance in direct redox-neutral radical C-H functionalization of heteroarenes. Herein, the direct C-H arylation, C-H alkylation, and C-H fluoroalkylation of heteroarenes are represented respectively, providing practical routes to C-C bond formation.