Copper‐Catalyzed One‐Pot Synthesis of 1,3,4‐Oxadiazol‐2(3H)‐ones using DMF as the Carbonyl Source

Abstract

A series of 1,3,4‐oxadiazol‐2(3H)‐ones were prepared by an efficient copper‐catalyzed one‐pot reaction of arylhydrazides, arylboronic acids and DMF. Moderate to good yield of 1,3,4‐oxadiazol‐2(3H)‐ones were obtained using DMF as the carbonyl source and arylboronic as the aryl source. This reaction involved ligand exchange and transmetalation of copper catalysts with arylhydrazides and arylboric acids, followed by reductive elimination and intramolecular cyclization. Compared to the previous work, this work employs the stable and readily available aryl hydrazide and arylboronic substrates that enhance the practicality of this strategy, and this strategy features a short reaction time, relatively low heating temperature, convenient and more secure. Further, this protocol has the features of high functional group tolerance and reaction scalability.