Synthesis of 3,5-Disubstituted 1,2,4-Oxadiazoles from Amidoximes and Aldehydes in the Superbasic System NaOH/DMSO

A new procedure has been proposed for the synthesis of 3,5-disubstituted 1,2,4-oxadiazoles by reaction of amidoximes with aldehydes in the superbasic system NaOH/DMSO at room temperature. The scope of the proposed procedure has been demonstrated by 15 syntheses from various amidoximes and aromatic aldehydes with 27–76% yields. The procedure is inapplicable to aliphatic aldehydes.