Zn(ANA)₂Cl₂ complex as efficient catalyst for the synthesis of dihydropyrano[2,3-c]pyrazoles in aqueous medium via one-pot multicomponent reaction: a green approach

The first example of recyclable Zn(ANA)₂Cl₂ catalyzed tandem one-pot three-component protocol reaction between aromatic aldehydes, malononitrile, and phenylmethylpyrazolone to furnish 4-substituted-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (4a–l) in a short reaction time (∼10 min) in aqueous media at room temperature is described.