Author(s): MA. El-ghamry*, AA. Saleh, SME. Khalil and AA. Mohammed
Bis(pyridylurea) ligand, EBPU and its Co(II), Ni(II), Cu(II), Fe(III), VO2+, UO2 2+ solid complexes were synthesized. Reaction of the ligand, EBPU with Co(II), Ni(II), Cu(II) and Fe(III) ions in presence of 8- hydroxyquinoline (8-HQ) afforded new mixed ligand complexes. The ligand and its metal complexes were characterized by elemental and thermal analyses, IR, 1H NMR, electronic and mass spectra as well as conductance and magnetic susceptibility measurements. The spectroscopic data showed that the ligand, EBPU acts as bi- and tetradentate toward the metal ions, coordination via the pyridine -N, the carbonyl -O and/or the amidic -N atoms in a non, monoand bis-deprotonated form. The metal complexes exhibited tetrahedral, octahedral and square pyramidal geometrical arrangements. Kinetic and thermodynamic parameters for the different thermal decomposition steps of some complexes were calculated using Coats–Redfern equation. 3D molecular modeling of the ligand, EBPU and a representative complex were studied.