The solid state synthesis of novel pyrazolyl-5-amino-pyrazole-4-carbonitrile derivatives using Fe3O4@SP@TA nanocomposites as a novel, green, and magnetically separable catalyst

Abstract

Tannic acid‐functionalized silica‐coated Fe3O4 nanocomposites (Fe3O4@SP@TA) were synthesized and characterized by transmission electron microscope (TEM), field emission scanning electron microscope (FE-SEM), X-ray powder diffraction (XRD), X-ray spectroscopy (EDX), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy (FT-IR). Fe3O4@SP@TA nanocomposite supplies an environmentally friendly procedure for the synthesis of some novel pyrazolyl-5-amino-pyrazole-4-carbonitrile through a three-component mechanochemical reaction of synthetized pyrazolecarbaldehydes, malononitrile, and phenylhydrazine according to green chemistry rules. These compounds were obtained in high yields and short reaction times. The catalyst could be easily recovered and reused for six cycles with almost consistent activity. The structures of the synthesized pyrazolyl-5-amino-pyrazole-4-carbonitrile compounds were confirmed by 1H NMR, 13C NMR, and FTIR spectral data and elemental analyses.