Catalyst‐ and Solvent‐Free Synthesis of N‐Acylhydrazones via Solid‐State Melt Reaction

Abstract We describe a fast, simple, and effective synthesis of N ‐acylhydrazones via a solid‐state melt reaction under catalyst‐ and solvent‐free conditions. The reactions of 2‐furoic hydrazide, 2‐thiophenecarboxylic acid hydrazide and substituted alkyl/aryl‐acylhydrazides with aromatic aldehydes proceeded well at 120 °C in only 30 min to give the corresponding products in good to excellent isolated yields (74–100%) without purification using column chromatography. Gram scale experiments also worked well. This method could be considered as a green procedure, which has a high atom economy (94.69–94.90%), high reaction mass efficiency (84.27–87.33%), low E‐factor (0.15–0.19 g/g), and low process mass intensity (13.21–14.30 g/g).