Catalysis Letters, Vol.144, No.8, 1393-1398, 2014
In Situ Generated Cetyltrimethylammonium Bisulphate in Choline Chloride-Urea Deep Eutectic Solvent: A Novel Catalytic System for One Pot Synthesis of 1,3,4-Oxadiazole
Cetyltrimethylammonium bisulphate ([CTA]HSO4) catalysed one pot synthesis of 2,5-disubstituted-1,3,4-oxadiazoles from carboxylic acid and acid hydrazide in biodegradable deep eutectic solvent is investigated. [CTA]HSO4 is generated in situ from cetyltrimethylammonium peroxodisulphate. Cyclization of diacylhydrazide using [CTA]HSO4 gives best alternative to traditional dehydration agents. Its remarkable features include a milder procedure, simplicity in workup and purification, good to excellent yields of products, use of inexpensive, recyclable reagents, and eco-friendly aspects by avoiding toxic catalysts/reagents and solvents. .
Keywords:Cetyltrimethylammonium peroxodisulphate;Deep eutectic solvent;Carboxylic acid;Acid hydrazide;1,3,4-Oxadiazole