nanomagnetite-fe3o4 is used as a highly efficient, mild, green and recyclable nanomagnetite catalyst for the synthesis of 4,4´-(arylmethylene)-bis(3-methyl-1-phenyl-1h-pyrazol-5-ol) derivatives in solvent-free conditions. the condensation reaction of 3-methyl-1-phenyl-1h-pyrazol-5(4h)-one with aromatic aldehydes affords the title compounds in high yields and short reaction times. the nanocataly...