Copper-Catalyzed One-Pot Synthesis of 2,5-Disubstituted 1,3,4-Oxadiazoles from Arylacetic Acids and Hydrazides via Dual Oxidation

Abstract

A simple and efficient protocol has been developed to access symmetrical and unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles from arylacetic acids and hydrazides via copper-catalyzed dual oxidation under an oxygen atmosphere. Oxidative decarboxylation of arylacetic acids and oxidative functionalization of the imine C–H bond are the key steps. This is the first example of the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles through dual oxidation in one-pot. Avoidance of the expensive ligand and high yield of the products are advantageous features of the developed method.

Unveiling the chemistry of 1,3,4‐oxadiazoles and thiadiazols: A comprehensive review

“…Thiadiazole and oxadiazoles are two important heterocyclic nitrogen‐containing scaffolds with broad‐spectrum biological activities like anticonvulsant, [ 1 ] antidiabetic, antituberculosis, diuretics, anticancer, anti‐inflammatory, antimicrobial, antiobesity, antiviral, antidepressant, antihypertensive, antileishmanial, insecticidal, herbicidal, analgesic, antioxidant, immunosuppressant, monoamine oxidase inhibitory, and urease inhibitory activities. [ 2 ]…”