ZnFe2O4 nanoparticles as a robust and reusable magnetically catalyst in the four component synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-4yl) (phenyl) methyl]propanedinitriles and substituted 6-amino-pyrano[2,3-c]pyrazoles

A simple method has been developed for the synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-4-yl)(phenyl)methyl]propanedinitriles and 6-amino-4-aryl-3-methyl-2,4-dihydro pyrano[2,3-c]pyrazole-5-carbonitrile derivatives through a one-pot four-component condensation reaction of aromatic aldehydes, malononitrile, ethyl acetoacetate and hydrazine hydrate using ZnFe2O4 nanoparticles under solvent-free conditions. This has the advantages of excellent yields, short reaction times, simple workup and environmentally benign.