46. An Electrocatalytic Strategy for Dehydrogenative [4+2] Cycloaddition over a Cobalt-Based Catalyst

Xue, X.,Wang, Y.,Zhou, L.,Ge, R.,Yang, J.,Kong, X.,Xu, M.,Li, Z.,Ma, L.,Duan, H.*
Chin. J. Chem. 2022, 40, 2741-2746.

Exploring the anodic reaction to substitute conventional oxygen evolution reaction (OER) for the synthesis of complex pharmaceutical molecules is highly attractive. Here, we report an electrocatalytic strategy for dehydrogenative [4 + 2] cycloaddition of N,N-dialkylanilines with maleimides via dual functionalization of both C(sp3)-H and C(sp2)-H bonds, by using an electrochemically activated cobalt carbonate hydroxide hydrate supported on carbon cloth (CCHH-A/CC), affording various tetrahydroquinolines with high yields. This electrochemical transformation proceeds with high activity and stability, as well as good substrate compatibility. Mechanism study shows that α-aminoalkyl radical exists in the electrooxidation reaction. This strategy shows significant potential for the synthesis of valuable chemicals by using an electrocatalytic strategy.