CuBr-catalyzed selective oxidation of N-azomethine: highly efficient synthesis of methine-bridged bis-indole compounds.

An efficient CuBr catalyzed cleavage of C-N bonds in the oxidative cross-dehydrogenative-coupling (CDC) of N-benzyl amines with indoles mediated by tert-butyl hydroperoxide (TBHP) was reported. A series of methine-bridged bis-indole derivatives were successfully synthesized under the optimized reaction conditions.