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The metal complex effect on the hydrogenation of chlorobenzene over a poly(N-vinyl-2-pyrrolidone)-stabilized platinum colloidal nanocatalyst (PVP-Pt) has been studied under 298 K and atmospheric pressure. The introduction of metal complexes and ligands exhibited great effect on the activity and the selectivity of the nanocatalyst. It is evidently manifested that the modification of metal complexes is not the simple sum of those of the metal central ions and the corresponding ligands.

Colloidal platinum–ruthenium bimetallic nanoparticles with 2.3 nm were synthesized in solution and then immobilized on tin dioxide powder to make a supported nanocatalyst (Pt–Ru/SnO 2 ). The immobilized bimetallic nanoparticles had the same size and size distribution as the solution dispersed ones. Selective hydrogenation of o -chloronitrobenzene to o -chloroaniline was performed over the as-prepared Pt–Ru/SnO 2 nanocatalyst without using any solvent; 99.5% selectivity to o -chloroaniline at ∼100% conversion was achieved.

The effect of metal ions on the hydrogenation of chlorobenzene over poly(vinylpyrrolidone)-stabilized platinum (PVP-Pt) colloidal catalysts was studied in methanol at 298 K and atmospheric pressure. It showed that some metal cations significantly affected the catalytic performances of the colloidal nanocatalysts. Almost all the metal cations studied decreased both the activity and the selectivity to cyclohexane, which might be due to the electron-deficient state of the surface Pt atoms resulting from the adsorbed metal ions. It is therefore essential to remove some metal ions, especially Sn2+, Cu2+, Zn2+, and Mn2+ from wastewaters for efficient catalytic hydrodechlorination.

Crystal structure of the title compound, [Ni(Im)6] (NO3)2·4H2O (Im = imidazole), was determined by X-ray crystallographic analysis. The crystal structure consists of discrete Ni(Im)26+ cation, NO−3 anion and four uncoordinated water molecules. It crystallizes in the hexagonal system, space group P63, with lattice parameters a = b = 0.9003(2) nm, c = 2.1034(4) nm, and Z = 2. The Ni(II) ion is centro- symmetric octahedron geometry with the NiN6 core. Six imidazole molecules are coordinated to each nickel (II) atom through its tertiary nitrogen atom. The short and long bond distances of Ni-N are 0.2059(6) and 0.2204(7) nm, respectively. In the solid state, [Ni(Im)6]2+, H2O moieties and nitrate anions form the three dimensional hydrogen bonds network which stabitizes the crystal structure.

The present work reports on the synthesis, characterization and performance of a new cobalt(II) complex, [Co(C10H21-bim)2(SCN)2] (bim = benzimidazole) as electrocatalyst for trichloroacetic acid and bromate reduction. Its structure was characterized by X-ray crystallography, IR spectroscopy and elemental analysis. The cobalt atom adopts a distorted tetrahedral geometry by coordinating to four nitrogen atoms from two thiocyanates and two 1-decyl-1H-benzo[d]imidazole ligands. The electrochemical behavior and electrocatalysis of the title complex bulk-modified carbon paste electrode (Co-CPE) have been studied by cyclic voltammetry. The Co-CPE shows good electrocatalytic activities toward the reduction of trichloroacetic acid and bromate. The detection limit and the sensitivity are 0.02 μM, 34.63 μA μM−1 for trichloroacetic acid detection, and 0.03 μM, 78.92 μA μM−1 for bromate detection, respectively. This modified electrode shows good reproducibility, high stability, low detection limit, technical simplicity and possibility of rapid preparation, which is important for practical application.

The bis(O,O′‐dibenzyldithiophosphato)Ni(II) adduct, [(PhCH2O)2PS2]2Ni(bpy), was synthesized by the reaction of [(PhCH2O)2PS2]2Ni with 2,2′‐bipyridine in the solid state. Single crystals of the title compound as the dihydrate were obtained by recrystallization in ethanol–distilled water (v/v = 9:1). The structure characterization was performed by means of IR, elemental analyses, and single crystal x‐ray analysis. The crystal of the title compound consists of two disconnected structural units, each of which includes two non‐coordination water molecules. The coordination geometry of each Ni atom is a distorted octahedron. The thermogravimetric (TG) data indicate that thermal decomposition of the title compound takes place in four steps and the residue is Ni(OPS2)2.

The structure of a new binuclear cadmium (II) complex, [Cd(H2O)2(Sal)2]2 (Sal= salicylate), has been determined by X-ray crystallography. It was also characterized by elemental analysis, its IR spectrum and thermogravimetric-differential scanning calorimetry (TG-DSC). It crystallizes in the monoclinic system, space group P2(1)/c, with lattice parameters a = 15.742(3) A, b = 12.451(3) A, c = 7.7225(15) A, beta = 96.07(3)degrees and Z = 4. Two cadmium (II) ions are bridged by two mu(2)-carboxy oxygen atoms. Each cadmium atom lies in a distorted capped octahedron coordination geometry. The thermal gravimetry (TG) data indicate that there are four discrete decomposition steps with two endothermic peaks and one exothermic peak. The final thermal decomposition product is CdO.

Two modifications of the α and β forms of bis(N-phenmethyl-benzimidazole-N)dichloro cobalt(II) complex, CoCl2(C7H5N2CH2Ph)2, have been obtained by reacting N-phenmethyl-benzimidazole with CoCl2 in different reaction solvents. X-ray analysis reveals that the two modifications have a similar molecular structure with different geometric parameters. The α-form crystallizes in triclinic, P—1 space group and the β form in the monoclinic, P21/c space group. The crystal structures of both consist of monomeric molecules of [CoCl2(C7H5N2CH2Ph)2] with slightly distorted tetrahedron geometry for the CoCl2N2 chromophore. They are also characterized by elemental analysis, i.r. spectrum, electronic spectrum, and thermogravimetric differential thermal analysis.

Three polymorphic, crystalline specimens of the bis(N-phenylmethylbenzimidazole-N)dichloro cobalt(II) complex CoCl2(C7H5N2CH2Ph)2 have been obtained from different solvents and their structures determined by X-ray diffraction. X-ray analysis revealed that the three compounds have the same composition; however, details of their molecular structure differ significantly. The α-form is triclinic, space group , with lattice parameters a = 10.396(2), b = 10.439(2), c = 13.665(3) A, α = 90.13(3), β = 110.15(3), γ = 110.46(3)°; both the β- and γ-forms crystallize in the monoclinic space group P21/c, with lattice parameters a = 12.884(3), b = 9.612(2), c = 21.761(7) A, β = 108.02(3)° for the β-form and a = 7.357(2), b = 18.337(4), c = 19.572(5) A, β = 107.46(3)° for the γ-form. In all three cases, the asymmetric unit consists of [CoCl2(C7H5N2CH2Ph)2] molecules. The geometry of their CoCl2N2 chromophore is a distorted tetrahedron. Thermogravimetric analysis (TGA) indicates that they have different thermal stabiliti...

In the title compound, [Co(C8H8NO2)2], the Co atom has a distorted square-planar coordination involving two N atoms and two O atoms from two ethanone 1-(2-hydroxyphenyl)oximato ligands. The molecular structure and packing are stabilized by intramolecular O—H...O hydrogen bonds and C—H...π intermolecular interaction.

In the title compound, [CuCl2(C6H5Cl2N)2], each Cu atom has a distorted tetra­hedral coordination involving two Cl− anions and two 2-chloro-5-(chloro­meth­yl)pyridine ligands. The mol­ecular structure and packing are stabilized by intra- and intermolecular C—H⋯Cl hydrogen-bonding inter­actions.

The title compound, [Pd(C14H12O2P)2]·CH2Cl2, consists of mononuclear [(Ph2PCH2COO)2Pd] complexes and dichloro­methane mol­ecules in a 1:1 molar ratio. The two (diphenyl­phosphino)acetate ligands are coordinated to the central Pd atom by their P and O atoms, forming five-membered chelate rings. The PdII atom has a distorted square-planar configuration [Pd—O = 2.076 (3) and 2.082 (3) A, and Pd—P = 2.214 (1) and 2.216 (1) A].

The title compound, [Cu2Cl2(C18H15O3P)4], is a centrosymmetric dinuclear complex, where each CuI atom has a distorted tetra­hedral coordination involving two triphenyl­phosphite ligands and two bridging Cl− anions. The mol­ecular structure and packing are stabilized by C—H⋯O and C—H⋯π inter­actions.

In the title compound, [Co(NCS)2(C4H6N2)2], each cobalt(II) ion is coordinated by two N atoms from two 2-methyl-1H-imidazole ligands and two N atoms from two iso­thio­cyanate groups. The Co atom lies on a mirror plane and adopts a slightly distorted tetrahedral coordination. The molecular structure and packing are stabilized by intramolecular and intermolecular hydrogen-bond interactions.

In the title compound, [Cd(N3)2(C10H8N2)2], the cadmium(II) ion is coordinated by two N atoms from two azide groups and four N atoms from two 2,2′-bi­pyridine ligands. The coordin­ation geometry of the cadmium(II) ion is distorted octahedral. The packing is stabilized by intermolecular C—H⋯N hydrogen-bond interactions.

The dinuclear (R,R)-tartrate nickel(II) complex, [Ni2((R,R)-C4H4O6)2(H2O)4]2·10H2O, has been synthesized and its crystal structure has been determined by single-crystal X-ray diffraction. The structure consists of two independent nickel (R,R)-tartrate units and ten water molecules. Each unit contains two (R,R)-tartrato dianions chelated to two nickel ions (5.049(2) and 4.994(2)A for Ni(1)-Ni(2) and Ni(3)-Ni(4)), with the use of two hydroxyl oxygen atoms and two carboxyl oxygen atoms as donor atoms. The coordination geometry for each nickel ion can be described as octahedral.

In the title compound, [Zn(N3)2(C10H8N2)2]·H2O, the zinc(II) ion is coordinated by two N atoms from two azide groups and four N atoms from two 2,2′-bi­pyridine ligands. The coordination geometry of the zinc(II) ion is slightly distorted octahedral. In the solid state, the title compound forms a network structure via hydrogen bonds.

The synthesis and X-ray structure of the novel tetranuclear copper(II) cluster compound [Cu4OCl6(BBIm)4] are reported. The four copper(II) atoms are located at the four vertexes of a tetrahedral skeletal structure, and an oxygen atom as an interstitial atom occupies the center position of the same tetrahedron; each edge of the Cu-Cu tetrahedron is bridged by one μ2-chlorine anion. The copper atom possesses a slightly distorted trigonal bipyramidal geometry with three μ2-Cl in an equatorial position and the interstitial O atom and one N atom from the 3-benzyl-benzimidazole ligand occupying axial positions. The Cu-Cu distances are in the range of 3.0986 - 3.1162A.

In the title compound, [ZnCl2(C6H4N3CH2COPh)2], the zinc ion is coordinated by two Cl− anions and two N atoms of two triazole ligands, forming a distorted tetrahedral geometry. The molecular structure and packing are stabilized by van der Waals interactions.