An Electrosynthesis of 1,3,4‐Oxadiazoles from N‐Acyl Hydrazones

The 1,3,4‐oxadiazole is a widely encountered motif in the areas of pharmaceuticals, materials, and agrochemicals. This work has established a mild, mediated electrochemical synthesis of 2,5‐disubstituted 1,3,4‐oxadiazoles from N‐acyl hydrazones. Using DABCO as the optimal redox mediator has enabled a mild oxidative cyclisation, without recourse to stoichiometric oxidants. In contrast to previous methods, this indirect electrochemical oxidation has enabled a broad range of substrates to be accessed, with yields of up to 83%, and on gram scale. The simplicity of the method has been further demonstrated by the development of a one‐pot procedure, directly transforming readily available aldehydes and hydrazides into valuable heterocycles.