Synthesis and Spectroscopic Characterization of Cobalt(II) and Nickel(II) Complexes with 5-Methyl-1-(2'-pyridyl)-pyrazole-3-carboxamide

摘要

A host of novel Co(II) and Ni(II) complexes with the 5-Methyl-1-(2'-pyridyl)pyrazole-3-carboxamide ligand (MPyPzCA) have been synthesized and characterized through analytical and physico-chemical data.Magnetic and electronic spectral studies classify the reported bis-chelates as 6 coordinated distorted octahedral ones.A scrutiny of the IR spectra between the ligand and its complexes and in analogy with the crystal structure analysis indicates that one ligand exercises neutral tridentate (NNO) behaviour through pyrazolyl 2N and pyridyl 1'N and amidic oxygen whereas the second ligand binds the same central metal atom through pyrazolyl 2N and pyridyl 1'N,respectively in the bis-chelates.The coordinated H2O molecule satisfies the sixth coordination site.The anions (X) in all the cases retain their ionic nature.