Complexation of metal ions with the novel 2-hydroxy-1-naphthaldehyde-derived diamine Schiff base carrying a macrobicyclic moiety with N2O2S2 mixed donor in acetonitrile-dichloromethane

Design and characterization of Cu(II) complexes from 2-benzoylpyridine benzhydrazone: crystallographic evidence for coordination versatility

The syntheses and characterization of six copper(II) complexes of 2-benzoylpyridine benzhydrazone in the form of [Cu(BPB)(2)], [Cu(BPB)Cl].H(2)O, [Cu(BPB)Br], [Cu(2)(BPB)(2)](ClO(4))(2).4H(2)O, [Cu(BPB)N(3)].H(2)O, and [Cu(BPB)NCS].H(2)O.CH(3)OH are reported. The analytical methods used for the characterization of complexes include partial elemental analyses, IR, electronic and EPR spectra, conductivity measurements, magnetic susceptibility measurements and single crystal X-ray diffraction. From the crystal structure, it is clear that the hydrazone adopts the E conformation about the azo bond to attach to the metal through the N(py)-N(azo)-O chelating system. In the EPR spectra of complexes in DMF at 77K four hyperfine quartets in the parallel region could be resolved and a half field signal is observed at 1500 G for complex [Cu(2)(BPB)(2)](ClO(4))(2).4H(2)O in polycrystalline state at 298 K which gives evidence for its binuclear nature indicating a weak interaction between the two Cu(II) ions.