Water-involving transfer hydrogenation and dehydrogenation of N-heterocycles over a bifunctional MoNi4 electrode

A room-temperature electrochemical strategy for hydrogenation (deuteration) and reverse dehydrogenation of N-heterocycles over a bifunctional MoNi4 electrode is developed, which includes the quinoxaline using H2O as hydrogen source with 80% Faradaic efficiency hydrogen-rich 1,2,3,4-tetrahydroquinoxaline up to 99% yield selectivity. The in situ generated active atom (H*) plausibly involved quinoxaline, where consecutive radical coupled electron transfer pathway proposed. Notably, alloy exhibits efficient at an overpotential only 50 mV, owing its superior water dissociation ability provide H* alkaline media. In Raman tests indicate that NiII/NiIII redox couple can promote process, representing promising anodic alternative low-value oxygen evolution. Impressively, electrocatalytic deuteration easily achieved ratios D2O. This method capable producing series functionalized hydrogenated deuterated quinoxalines.