Synthesis and characterization of binuclear metal complexes derived from some isonitrosoacetophenones and benzidine

Abstract

The complexes of Co(ll), Ni(II) and Cu(II) with 2-hydroxyimino-1-[<i>p</i>-aminobiphenylimino]-1-(4¢- X-phenyl)glyoxal (X=H, Cl, Br, CH₃), abbreviated as <i>p</i>-X-HABPG, have been synthesised <i>in situ </i> by the reaction of isonitrosoacetophenones, benzidine and metal chloride. The complexes have been characterized by various physicochemical methods. The analytical data correspond to the general formula M₂L₂Cl₂ 4H₂O [M = Co(ll), Ni(II) and Cu(Il)). The electrical conductance in nitrobenzene solution indicates their non-ionic nature. The room temperature magnetic susceptibility measurements suggest an octahedral geometry for all the complexes, which is further supported by their diffuse reflectance spectra. Various ligand field parameters have been calculated for Co(II) and Ni(II) complexes. The infrared spectra of the complexes indicate bonding through imino and oximino nitrogen and also shows involvement of the terminal-NH₂, group in coordination to the metal.