A Fast and Highly Efficient Protocol for Synthesis of Dihydropyrano[2,3]PyrazoleCompounds Using Acidic Ionic Liquid 3-Methyl-1-Sulfonic Acid Imidazolium Chloride ([Msim]Cl)as Catalyst and Green Solvent


Department of Chemistry, Faculty of Science, Shahid Bahonar University of Kerman, Kerman, Iran


A new, efficient, and environmentally benign protocol for the one-pot, four-component synthesis of dihydropyrano[2,3-c]pyrazoles by condensation of ethylacetoacetate, hydrazine hydrate, aromatic aldehyde, and malononitrile catalyzed by3-methyl-1-sulfonic acid imidazolium chloride([Msim]Cl) as an ecofriendly catalyst with high catalytic activity and reusability at 30 0C under solvent-free conditions is reported. The reactions proceed to completion within 5–15 min in 87–97% yield.