An unexpected Schiff base-type Ni(II) complex: synthesis, crystal structures, fluorescence, electrochemical property and SOD-like activities.

An unexpected Schiff base-type Ni(II) complex, [Ni(L(2))2]⋅CH3OH (HL(2) = 1-(2-{[(E)-3, 5-dibromo-2-hydroxybenzylidene]amino}phenyl)ethanone oxime), has been synthesized via complexation of Ni(II) acetate tetrahydrate with HL(1) (2-(3,5-dibromo-2-hydroxyphenyl)-4-methyl-1,2-dihydroquinazoline 3-oxide) originally. HL(1) and its corresponding Ni(II) complex were characterized by IR, (1)H NMR spectra, as well as by elemental analysis, UV-Vis and emission spectroscopy, respectively. Crystal structures of the ligand and complex have been determined by single-crystal X-ray diffraction. Each complex links two other molecules into an infinite 1-D chain via intermolecular hydrogen bonding interactions. Moreover, the electrochemical property of the nickle complex was studied by cyclic voltammetry. In addition, SOD-like activities of HL(1) and Ni(II) complex were also investigated.

An unexpected cobalt(III) complex containing a Schiff base ligand: Synthesis, crystal structure, spectroscopic behavior, electrochemical property and SOD-like activity.

An unexpected mononuclear Co(III) complex, [Co(L2)2·(CH3COO)]·CH3OH (HL2=1-(2-{[(E)-3,5-dichloro-2-hydroxybenzylidene]amino}phenyl)ethanone oxime), has been synthesized via complexation of Co(II) acetate tetrahydrate with HL1 originally. The plausible reaction mechanism for the formation of quinazoline-type ligand was proposed. HL1 and its corresponding Co(III) complex were characterized by IR, as well as by elemental analysis and UV-vis spectroscopy. The crystal structure of the complex has been determined by single-crystal X-ray diffraction. Each complex links two other molecules into an infinite 1-D chain via intermolecular hydrogen bonding interactions. Moreover, the electrochemical properties of the cobalt(III) complex were studied by cyclic voltammetry and X-ray photoelectron spectrum (XPS). In addition, superoxide dismutase-like activities of HL1 and Co(III) complex were also investigated.

Bis[(E)-4-bromo-2-(methoxy-imino-meth-yl)phenolato-κN,O]copper(II).

In the title centrosymmetric mononuclear copper(II) complex, [Cu(C(8)H(7)BrNO(2))(2)], the Cu(II) atom, lying on an inversion centre, is four-coordinated in a trans-CuN(2)O(2) square-planar geometry by two phenolate O atoms and two oxime N atoms from two symmetry-related N,O-bidentate oxime-type ligands. Inter-molecular C-H⋯O hydrogen bonds link neighbouring mol-ecules into a one-dimensional supra-molecular structure with an R(2) (2)(14) ring motif. This structure is further stabilized by π-π stacking inter-actions between adjacent benzene rings [centroid-centroid distance = 3.862 (1) Å].

3,3'-Bis(4-nitro-phen-yl)-1,1'-(p-phenyl-ene)dithio-urea dimethyl sulfoxide disolvate.

The asymmetric unit of the title compound, C(22)H(16)N(6)O(6)S(2)·2C(2)H(6)OS, consists of one half-mol-ecule of the centrosymmetric thiourea derivative and one molecule of dimethyl sulfoxide (DMSO). The carbonyl group forms an intra-molecular hydrogen bond with the NH group, creating a six-membered (C-N-C-N-H⋯O) ring. Two other N-H⋯O hydro-gen bonds link one mol-ecule of the thio-urea to two mol-ecules of DMSO.

N-(2-Chloro-benzo-yl)-N'-(3-pyrid-yl)thio-urea.

In the mol-ecule of the title compound, C(13)H(10)ClN(3)OS, the dihedral angles between the plane through the thio-urea group and the pyridine and benzene rings are 53.08 (3) and 87.12 (3)°, respectively. The mol-ecules are linked by inter-molecular N-H⋯N hydrogen-bonding inter-actions to form a supra-molecular chain structure along the a axis. An intra-mol-ecular N-H⋯O hydrogen bond is also present.