Transition Metal-Mediated Direct CH Arylation of Heteroarenes Involving Aryl Radicals

This review gives an overview of the generation of aryl radicals, mediated by transition metals, and their use for the CH arylation of heteroarenes. The different sources of aromatic derivatives able to generate aryl radicals via a metal‐assisted reduction or oxidation are discussed, with a critical view of the developed systems. The radical arylations of nitrogen‐, oxygen‐ or sulfur‐containing heterocycles are then described and mechanistic considerations are discussed as well.