Rapid Synthesis of Polyfunctionalized Pyrano[2,3-c]pyrazoles via Multicomponent Condensation in Room-Temperature Ionic Liquids

Abstract

A highly efficient synthesis of 4H-pyrano[2,3-c]pyrazoles has been completed using four-component cyclocondensation of hydrazine monohydrate/phenyl hydrazine, ethyl acetoacetate, aldehydes, and malononitrile in the presence of L-proline and room-temperature ionic liquids.

Keywords:

• 1-Butyl-3-methylimidazolium tetrafloroborate
• clean synthesis
• combinatorial chemistry
• heterocycles
• pyrano[2,3-c]pyrazoles

ACKNOWLEDGMENTS

Financial assistance by the Council of Scientific and Industrial Research, New Delhi, India, as a junior research fellowship to Bhaskara Nand and junior and senior research fellowships to Sanjay Kumar is gratefully acknowledged.