Photocatalytic C-H Amination of Aromatics Overcoming Redox Potential Limitations.

We report the photocatalytic C-H amination of aromatics overcoming redox potential limitations. Radical cations of aromatic compounds are generated photocatalytically using Ru(phen)3(PF6)2, which has a reduction potential at a high oxidation state (Ered(RuIII/RuII) = +1.37 V vs SCE) lower than the oxidation potentials of aromatic substrates (Eox = +1.65 to +2.27 V vs SCE). The radical cations are trapped with pyridine to give N-arylpyridinium ions, which were converted to aromatic amines.