Spectroscopic, thermal and magnetic properties of some transition metal complexes derived from 1-Phenyl-3-Substituted-4-Nitroso-5-Pyrazolones

Complexes derived from some 1Phenyl3meth yl4nitroso5pyrazolone (L1), 1,3diphenyl4 nitroso5pyrazolone (L2) and 1phenyl3anilino 4nitroso5pyrazolone (L3) with Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ metal ions have been prepared. Structural investigation of the ligands and their complexes has been made based on elemental analysis, infrared (FTIR), ultraviolet and visible spectra (UVVis.), proton nuclear magnetic reso nance (1H NMR), magnetic susceptibility (?eff.) and thermal analysis (TG and DTG). The effect of solvents has been carried out in organic solvents of varying polarity. The observed transition energy and oscillator strengths were also calculated. The data obtained show that all of the prepared complexes contain water molecules in their coordination sphere. The investigated ligands acts as neutral bidentate ligands bonded to the metal ions through the two oxygen atoms of the carbonyl and nitroso groups. The isolated complexes behave as nonelectro lyte in DMF solution. The Mn2+, Co2+, Ni2+ and Cu2+ complexes show high spin configurations as the ground state. The high spin values of ma gnetic susceptibility may be due to the ligands being weak ligands. The Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ complexes exhibit an octahedral or distorted octahedral coordination with the investigated ligands.