Direct Radical Arylation of Unactivated Arenes Using Phenyl Hydrazine

Studer et al. have reported the direct radical arylation of unactivated arenes using phenylhydrazine as an initiator. According to their results, in the presence of catalytic amounts of phenylhydrazine and a base, unactivated arenes react with aryl iodides involving aryl radicals and aryl radical anions as intermediates, and the corresponding biaryls are produced in high yields. This reaction is expected to be a useful synthetic method for various substituted biaryls because the reaction is carried out under relatively mild reaction conditions with a low initiator loading.