Synthesis and Characterization of Cu(II), Ni(II) and Cd(II) Complexes With 3,5-Diamino-4-(4-Bromo-Phenylazo)-1H-Pyrazole

Abstract

3,5-Diamino-4-(4-bromo-phenylazo)-1H-pyrazole (L) ligand have been synthesized from 2-(4-bromo-phenylazo)malononitrile and hydrazine hydrate. Complexes of this ligand with Cu(II), Ni(II) and Cd(II) chloride were prepared. The structures of the ligand and its complexes are proposed based on the elemental analyses, IR, 1 H and 13C NMR spectra, UV-Vis. spectra, thermogravimetric analyses (TGA), differential thermal analyses (DTA) and magnetic susceptibility measurements. Magnetic moments, along with electronic spectral data, suggest octahedral geometry for the Ni(II), for the a tetrahedral structure Cd(II) complex, whereas, squareplanar structure has been proposed for the Cu(II) complex. Thermal decomposition of complexes ended with metal oxide as a fi nal product.