An iodine-mediated green synthesis of 1,3,4-oxadiazoles under solvent-free conditions using grinding technique

Abstract

An eco-friendly efficient synthesis of symmetrical and unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles is described through the reaction of aromatic hydrazides with aryl aldehydes obtained by grinding them in the presence of catalytic amounts of molecular iodine in a mortar in a single step. The present method avoids the isolation of N-acyl hydrazones prior to their oxidative cyclization and avoids the use of organic solvents at any stage of the reaction.