Facile Synthesis of Unsymmetrical 2,5‐Disubstituted 1,3,4‐Oxadiazoles by Cyclization of gem‐Difluoroalkenes with Acyl Hydrazides

Abstract A mild and efficient method for the synthesis of unsymmetrical 2,5‐disubstituted 1,3,4‐oxadiazoles by condensation of gem ‐difluoroalkenes with acyl hydrazides was developed. The cyclization reaction proceeds smoothly with the assistance of Cs 2 CO 3 , affording a variety of 1,3,4‐oxadiazoles in good to excellent yields. The reaction also exhibits a broad substrate scope and good functional group compatibility.