Synthesis of a New Thiourea Derivative Substituted 5,6-Diamino-1,10-phenanthroline and Crown Ether and Its Complexes with Copper(II), Nickel(II) and Cobalt(II)

A new thiourea derivative ligand (LH2), 6-amino-5-ylamino-benzo[15-crown-5]-15- ylaminoethanethione[1,10]phenanthroline has been synthesized in the reaction of 5,6-diamino-1,10-phenanthroline with 15-isothiocyanatobenzo[15-crown-5] and its metal complexes with Cu(II), Ni(II) and Co(II) have been prepared. The structures and compositions of the ligand and the complexes have been confirmed by elemental analyses, UV-vis, FTIR, 1H NMR (DMSO-d6), 13C NMR (DMSO-d6), mass spectra (LC-MS) andmagnetic measurements. The metal to the ligand ratio of the Cu(II), Ni(II) and Co(II) complexes have been found to be 1:2. Protonation constants of the ligand and overall formation constants of the complexes have been calculated from potentiometric data using the computer program.