Three‐Component One‐Pot Synthesis of 1,4‐Dihydropyrano[2,3‐<i>c</i>]pyrazole Derivatives in Aqueous Media

Abstract

Abstract 6‐Amino‐5‐cyano‐4‐aryl‐1,4‐dihydropyrano[2,3‐c]pyrazoles were synthesized by three‐component reaction of aromatic aldehydes, malononitrile, and 3‐methyl‐1‐phenyl‐2‐pyrazolin‐5‐one using triethylbenzylammonium chloride (TEBA) as catalyst in aqueous media. The reaction has the advantages of good yield, less pollution, ease of separation, and of being environment friendly.