Greener approach towards the facile synthesis of 1,4-dihydropyrano[2,3-c]pyrazol-5-yl cyanide derivatives at room temperature

This report describes triethylammonium acetate (TEAA) ionic liquid catalyzed one pot synthesis of 6-amino-4-aryl-5-cyano-3methyl-l-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles by the reaction of aromatic aldehyde, malononitrile and 3-methyl-1-phenyl-2-pyrazolin-5-one at room temperature. TEAA plays dual role as reaction media and catalyst. It can also be easily recovered and reused in several runs. TEAA provides greener reaction protocol to present methodology which obviates the need of organic solvents, expensive and toxic catalyst. (C) 2010 Dhananjay V. Mane. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.