Room temperature, open-flask C-H arylation of electron-deficient heteroarenes with triazenes: Rapid synthesis of heterobiaryls

Aryl triazenes, a source of aryl radicals, were coupled with heteroarenes via C-H functionalization to produce heterobiaryls in moderate to good yields. Couplings proceeded under an open atmosphere at ambient temperature for 3-24 h. Best results were obtained with electron-deficient heteroarenes, while both electron donating and withdrawing substituents in the triazene moieties were tolerated.