Intermolecular direct arylation of five-membered ring heterocycles by non-activated aryl chlorides

The use of non-activated aryl chloride electrophiles in the direct arylation of carbon–hydrogen bonds in five-membered ring heterocycles is described. Specifically, palladium-, ruthenium-, and nickel-catalyzed transformations, as well as reactions proceeding via benzyne intermediates, are discussed.