Publication: Synthesis, thermal studies and spectral characterization of Co(II), Ni(II), Cu(II), and Zn(II) complexes with some polymeric diacetyl acyldihydrazone ligands
Loading...
Date
2013
Journal Title
Macromolecular Research
Journal ISSN
Volume Title
Publisher
Abstract
Two polymeric ligands, diacetyl oxaloyldihydrazone (DODH), diacetyl malonoylhydrazone (DMDH) and their Co(II), Ni(II), Cu(II) and Zn(II) complexes were synthesized and characterized by elemental analyses, IR, mass, 1H & 13C NMR, ESR and electronic spectral studies. The ligands and their complexes are highly insoluble in water and common organic solvents and decompose at high temperature. The metal atoms are embedded between two polymeric chains of the organic ligands and the monomeric unit of the polymeric chain behaves as a neutral bidentate ligand and coordinate through two >C=N groups to different metals as indicated by 1H & 13C NMR and IR spectral studies. The molecular weights determined by 1H NMR and mass spectral studies suggest oligomeric nature of the ligands and their Zn(II) complexes. The magnetic susceptibility measurements and electronic spectral studies indicate a square planar geometry around the metal ion in Co(II) and Ni(II) complexes. Electronic and ESR spectral studies for Cu(II) complexes suggest a distorted octahedral stereochemistry around the metal atom and 2B1g as the ground state. Thermal studies (TGA and DTA) of some of the complexes in inert atmosphere show a multi-step exothermic decomposition of the bonded organic ligand at high temperature and metal (II) chloride as the end product. © 2013 The Polymer Society of Korea and Springer Sciene+Business Media Dordrecht.
Description
Keywords
acyldihydrazones, ESR spectra, mass spectrometry, NMR spectra, polymeric metal complexes, thermal studies