Environmentally benign synthesis of methyl ۶-amino-۵-cyano-۴-aryl-۲,۴-dihydropyrano[۲,۳-c]pyrazole-۳-carboxylates using CeO۲ nanoparticles as a reusable and robust catalyst

چکیده مقاله

In this work, we report the synthesis and characterization of CeO2 nanoparticles as an efficient catalyst for the preparation of methyl 6-amino-5-cyano-4-aryl-2,4- dihydropyrano[2,3-c]pyrazole-3-carboxylates via one-pot four-component condensation reaction of dimethyl acetylenedicarboxylate, hydrazine hydrate, malononitrile, and aldehydes in aqueous medium. The use of a non-hazardous organic solvent, easy recovery of the catalyst, compatibility with various functional groups, and high yield of the products make the protocol attractive, greener, and economic.