Electrochemical oxidative carbonylation of hydrazides for the synthesis of 1,3,4-oxadiazole-2(3H)-ones

We have developed an electrochemical method for the synthesis of 1,3,4-oxadiazole-2(3H)-ones using CO (carbon monoxide) as the carbonyl source under undivided electrolytic conditions. The electrochemical oxidative carbonylation of hydrazides features mild, green and external oxidant-free conditions, broad substrate scope, a short reaction time and ease of scale-up to the gram scale. Both control experiments and mechanistic studies revealed that no radical process was involved in this electrochemical transformation.