C–C and C–N bond formation in electro-oxidation reactions of aromatic compounds

Abstract

Atom-economical, eco-efficient, metal- and chemical oxidant-free formation of C–C and C–N bond from C(sp2)−H and C(sp3)−H of arenes toward the direct synthesis of biaryls and anilides or N-benzylamides under mild electro-oxidative conditions is described. The products of C–C and C–N coupling are obtained in up to 88% yields. Aromatic substrates that are oxidized at potentials less positive than +2 V or have bulky bromine or iodine substituents undergo homo-coupling reactions by anodic oxidation to form biaryls or dimers. Aromatic substrates that are difficult to oxidize (Eox > +2 V) preferentially form anilides and N-benzylamides upon anodic oxidation. The presence of a chlorine substituent on the aromatic ring leads to the formation of both biaryls and anilides during electro-oxidation.

Keywords

• Electro-oxidation
• C–H functionalization
• C–C coupling
• C–N bond formation
• Metal-free
• Biaryl