Abstract
Copper (II) complexes of both 2-(2-(4-hydroxy-3-methoxybenzylidene) hydrazinyl)-2-oxo-N-phenylacetamide (H2L1) and 2-(2-(2-hydroxy-3-methoxybenzylidene) hydrazinyl)-2-oxo-N-phenylacetamide (H2L2) have been prepared and investigated by analytical, magnetic and spectroscopic techniques. IR spectra displayed that (H2L1) behaves as mono-negative tridentate or mono-negative tetradentate in both of [Cu(HL1)Cl]·(2H2O) and [Cu2(HL1)Cl3(H2O)](1.5H2O), respectively. But (H2L2) behaves as neutral bidentate or bi-negative pentadentate in both of [Cu(H2L2)2Cl2]·(2H2O) and [Cu2(L2)Cl2(H2O)]·(2H2O), respectively. 1H NMR spectra showed the replaceable hydrogens of the prepared ligands. The magnetic moment values helped to investigate the geometry of the complexes. Thermogravimetric studies gave a general pattern for the main stages of the thermal decomposition with kinetic data to evaluate thermodynamic parameters ΔH* and ΔG* for each step of degradation to compare between stability of those complexes. Also pH-metric measurements were used to evaluate the proton–ligand formation constants and the stability constants of metal complexes at 298°K. Floatation procedure was carried out to investigate the optimum conditions for Cu(II) separation by ligand molecules.
•A series of Cu(II) complex was prepared.•The solid complexes were investigated using different spectral and analytical tools.•The pH-metric measurements were used to evaluate the protonation and formation constants.•Floatation used to optimize the separation conditions of Cu(II) ion using defiant sensor