Cathode Material Determines Product Selectivity for Electrochemical C?H Functionalization of Biaryl Ketoximes
The synthesis of polycyclic N-heteroaromatic compounds and their corresponding N-oxides has been developed through electrochemical C?H functionalization of biaryl ketoximes. The oxime substrates undergo dehydrogenative cyclization when a Pt cathode is used, resulting in unprecedented access to a wide range of N-heteroaromatic N-oxides. The products of the electrosynthesis are switched to the deoxygenated N-heteroaromatics by employing a Pb cathode through sequential anode-promoted dehydrogenative cyclization and cathodic cleavage of the N?O bond in the initially formed N-oxide.