Green and Efficient Synthesis of Pyrazole-Conjugated Chromene Derivatives

Abstract

Pyrazolyl-substituted chromene analogues have been synthesized in one pot from 1H-pyrazole-5-carbaldehydes, malononitrile, and cyclohexane-1,3-dione or dimedone in the presence of L-proline as catalyst using ethanol as solvent under reflux conditions for 2–3 h. This approach offers notable advantages such as high yields, environmental friendliness, easy experimental procedure, short reaction time, and mild reaction conditions.