Synthesis, characterization and extraction studies of N,N″-bis[1-biphenyl-2-hydroxyimino-2-(4-acetylanilino)-1-ethylidene]-diamines and their homo-and heteronuclear copper(II) complexes

Abstract

A new series of homo- and heteropolynuclear copper(II) complexes of N,N″-bis[1-biphenyl-2-hydroxyimino-2-(4-acetylanilino)-1-ethylidene]-diamines have been prepared and characterized by different physical techniques. The starting point of the research was the reaction of chloroacetyl chloride with biphenyl in the presence of aluminum chloride. 4-Biphenylhydroximoyl chloride was obtained by reacting synthesized 4-(chloroacetyl)biphenyl with alkyl nitrite. Substituted 4-(alkylaminoisonitrosoacetyl) biphenyl (ketooxime) was prepared by reacting 4-biphenylhydroximoyl chloride with 4-aminoacetophenone in EtOH. Homodi-, homotrinuclear and heterodinuclear copper(II) perchlorate complexes of tetradentate Schiff bases which possess N4 donor sets derived from the condensation of 4-(arylaminoisonitrosoacetyl)biphenyl and diamine derivatives were synthesized and characterized. Elemental analysis, FT-IR, ESR, molar conductivity, magnetic moment measurements and thermal analyses studies were utilized for the investigation of the complexes. The free ligands were also characterized by 1H- and 13C-NMR spectra. Elemental analyses, stoichiometric and spectroscopic data of the metal complexes indicated that the metal:ligand ratio of dinuclear copper(II) complexes were found to be 2: 1 while this ratio was 3: 2 in trinuclear copper(II) complexes and the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms. The extraction abilities of the novel ligands were also evaluated in chloroform by using several transition metal picrates such as Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+, Cd2+, Hg2+. It has been observed that both ligands show a high affinity to Cu2+ ions.