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Bis(1H-benzimidazole-κN3)bis[2-(naphthalen-1-yl)acetato-κ2O,O′]nickel(II) monohydrate  [cached]
Fu-Jun Yin,Li-Jun Han,Zhao Hong,Xing-You Xu
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812010021
Abstract: In the title compound, [Ni(C12H9O2)2(C7H6N2)2]·H2O, The NiII cation is located on a twofold rotation axis and is six-coordinated in a distorted NiN2O4 octahedral geometry. The asymmetric unit consists of a nickel(II) ion, one 2-(naphthalen-1-yl)acetate anion, a neutral benzotriazole ligand and one half of a lattice water molecule. The crystal packing is stabilized by O—H...O and N—H...O hydrogen bonds. The title compound is isotypic with its CdII analogue.
Synthesis and characterisation of Manganese (II), Cobalt (II), Nickel (II) and Copper (II) N,N'-bis(Benzoin)ethylenediiminato complexes
HN Aliyu, HJ Abdullahi
Bayero Journal of Pure and Applied Sciences , 2009,
Abstract: The manganese (II), cobalt (II), nickel (II) and copper (II) complexes of N, N’ –bis(benzoin)ethylenediiminato have been prepared and characterized by infrared, elemental analysis, conductivity measurements and solubility. The potentiometric, and elemental analyses studies of the complexes revealed 1:1 metal to ligand ratio.
Bis(2-aminopyridine-κN1)bis(benzoato-κO)cobalt(II)
Di-Chang Zhong,Gui-Quan Guo,Xiao-Hua Zuo,Ji-Hua Deng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807063933
Abstract: In the title compound, [Co(C7H5O2)2(C5H6N2)2], the CoII atom is hexacoordinated by four O atoms from two benzoate anions, and two N atoms from two 2-aminopyridine molecules, resulting in a distorted octahedral geometry. Both benzoate anions act as bidentate ligands and both 2-aminopyridine molecules are coordinated to the metal through their pyridyl N atoms. The crystal packing is stabilized by intermolecular N—H...O hydrogen bonds, C—H...π, and π–π stacking interactions involving benzoate anions and 2-aminopyridine molecules.
Studies on Bis(Para Anisidine Acetylacetonato) Nickel (II) Complex
HN Aliyu, UL Bilyamin
Bayero Journal of Pure and Applied Sciences , 2011,
Abstract: Schiff base was prepared from the reaction of para anisidine and acetylacetone. Bis(para anisidineacetylacetonato)nickel(II) complex was synthesized by the reaction of the prepared para anisidineacetylacetone ligand and nickel(II) chloride. The prepared Schiff base is orange yellow, has a yield of 61.90% and melting point of 86oC. The complex prepared is red, has a yield of 71% and decomposition temperature of 270oC. The para anisidineacetylacetone ligand is soluble in water and most organic solvents, similarly, its nickel(II) complex compound is soluble in most solvents except water and methanol, in which it slightly soluble. The molar conductance of bis(para anisidineacetylacetonato)nickel (II) complex compound determined is 4.70 ohm-1 cm2mol-1, suggesting that the complex is non-electrolyte. The infra-red spectral data of para anisidine and acetylacetone base showed a medium size band in the range 1595 – 1630cm-1, attributable to v(C=N) stretching vibrations, the same band is observable in the nickel(II) complex, indicating coordination of the ligand to the nickel(II) ion. The broad band in the range 3257 - 3420 cm-1 observed in para anisidineacetylacetone ligand is assigned to v(O-H) stretching vibrations, which is absent in anisidineacetylacetonato)nickel(II) complex, as a result of deprotonation of the para anisidineacetylacetone on coordination to the nickel(II) ion. The dissociation constant (pKa) of para-anisidine acetylacetone determined is 12.66. The stability constant of anisidineacetylacetonato)nickel (II) complex compound determined is 1.29x106 and the corresponding Gibb’s free energy of complex is -3.48 x104 KJ per mole. The average number of para anisidine ligand coordinated to nickel(II) ion determined using potentiometer is 2, suggesting a four coordinate complex compound.
Bis(acetato-κO)bis(pyridine-2-aldoxime-κ2N,N′)nickel(II)  [cached]
Youtao Si
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812014377
Abstract: In the mononuclear title compound, [Ni(CH3COO)2(C6H6N2O)2], the NiII atom is coordinated by two pyridine-2-aldoxime (PaoH) ligands and two acetate groups, with cis coordination for the pairs of identical ligands. While each acetate group binds to the NiII atom by one O atom, each PaoH chelates the NiII atom through two N atoms. The O atom on PaoH is not deprotonated and does not participate in bonding to the NiII atom. Thus, the NiII atom exhibits an octahedral environment. Intramolecular O—H...O hydrogen-bonding interactions and intermolecular C—H...O hydrogen-bonding interactions are present in the structure. Adjacent molecules pack along [100] through van der Waals forces.
trans-Bis(acetato-κO)bis(2-aminoethanol-κ2N,O)nickel(II)  [cached]
Mahdi Seifollahi Bazarjani,Sabine Foro,Wolfgang Donner,Aleksander Gurlo
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812014237
Abstract: In the title compound, [Ni(CH3CO2)2(C2H7NO)2], the NiII cation, located on an inversion center, is N,O-chelated by two 2-aminoethanol molecules and further coordinated by two monodendate acetate anions in a slightly distorted octahedral geometry. The latter is stabilized by intramolecular O—H...O hydrogen bonds involving the non-coordinated O atom of the acetate and the H atom of the hydroxy group of the 2-aminoethanol ligand. In the crystal, N—H...O hydrogen bonds link the molecules into a three-dimensional supramolecular framework that involves (a) the coordinated acetate O atom and one of the H atoms of the amino group and (b) the non-coordinated acetate O atom and the other H atom of the amino group.
Redetermination of bis(2-formylphenolato-κ2O,O′)nickel(II) as bis[2-(iminomethyl)phenolato-κ2N,O′]nickel(II)  [cached]
Sylvain Bernès
Acta Crystallographica Section E , 2010, DOI: 10.1107/s160053680905483x
Abstract: The crystal structure of bis(2-formylphenolato-κ2O,O′)nickel(II), [Ni(C7H5O2)2], a square-planar centrosymmetric complex, has been reported previously [Li & Chen (2006). Acta Cryst. E62, m1038–m1039]. However, a number of warning signs allows the assumption that the carbonyl group in the salicylaldehydate ligand of the claimed complex is incorrect. The crystal structure was therefore redetermined on basis of the originally deposited structure factors. After substituting the carbonyl O atom by an N atom, the model can be completed with an imine H atom, which was clearly discernible in a difference map. The resulting model, corresponding to bis[2-(iminomethyl)phenolato-κ2N,O′]nickel(II), [Ni(C7H6NO)2], converges well and none of the previous structural alerts remains. This reinterpretation is also consistent with the published synthesis, which was carried out using salicylaldehyde in the presence of aqueous NH3. The reinterpreted structure is virtually identical to earlier reports dealing with this bis-iminato NiII complex.
Synthesis, Characterization, and X-Ray Structure of Bis(O-butyldithiocarbonato)bis(3-ethyl pyridine)nickel(II)  [PDF]
Inderjeet Kaur,Kuldeep Singh,Gurvinder Kaur,Renu Sachar,Vivek K. Gupta,Rajni Kant
Journal of Crystallography , 2014, DOI: 10.1155/2014/642839
Abstract: A new series of additional complexes of bis(O-butyldithiocarbonato)nickel(II) with ethylpyridines have been prepared and characterized by physicochemical techniques like elemental analysis, molar conductance measurements, TGA-DTA and UV-visible electronic spectroscopy, and IR-spectral data. The structure of [Ni(S2COC4H9)2(C7H9N)2] has been established by X-ray crystallography. The complex crystallizes in the monoclinic space group P1/n with unit cell parameters , , and ?? and , , and °. The Ni atom in the title complex is octahedrally coordinated within a trans-N2S4 donor set, with the Ni atom located on a centre of inversion. Crystal structure was solved by direct methods and refined by full matrix least squares procedures to a final -value of 0.0545 for 1984 observed reflections. The butyl chain is disordered over two sets of sites, with occupancy ratio of 0.572?:?0.427. 1. Introduction O-alkyldithiocarbonate ( ), named xanthate, represents an important class of 1, 1 dithiolato ligands which have been studied extensively [1, 2]. These compounds form water insoluble complexes with most of the transition metals and are thus extensively employed for the separation and quantitative determination of cations of transition metals [3]. Beside this these ligands are also investigated for nonlinear optical application and as a synthetic precursor for the generation of metal sulfide nanoparticles [4, 5]. Xanthates as ligand are also extensively studied for a wide variety of structural features. They are known to coordinate as a monodentate, bidentate, or as a bridging ligand. Xanthate complexes of composition [Ni(Rxa)2] (R = alkyl; xa = xanthate) are partially unsaturated and thus they can react easily with monodentate or bidentate nitrogen donor ligands and afford octahedral nickel(II) complexes with either cis or trans geometry. As a part of our ongoing research on nickel(II) xanthate complexes with substituted pyridines, we report here the synthesis and characterization of 1?:?2 adducts of bis(O-butyldithiocarbonato)nickel(II) with ethyl pyridines and also the crystal structure of the adduct bis(O-butyldithiocarbonato)bis(3-ethylpyridine)nickel(II). 2. Experimental 2.1. Material and Measurement Carbon, hydrogen, sulphur, and nitrogen contents of the addition complexes are determined on elemental analyzer CHNS 932, LECO Corporation, USA. Molar conductance of adducts was determined on their millimolar4 solutions in DMF by using digital conductivity meter “Century CC 601.” Infrared spectra of the complexes over the region 4000–200?cm?1 were recorded using KBr
Di-μ-acetato-bis[(acetato-κ2O,O′)bis(isonicotinamide-κN)copper(II)]
Mireille Perec,Ricardo Baggio
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810004393
Abstract: The title centrosymmetric bimetallic complex, [Cu2(C2H3O2)4(C6H6N2O)4], is composed of two copper(II) cations, four acetate anions and four isonicotinamide (INA) ligands. The asymmetric unit contains one copper cation to which two acetate units bind asymmetrically; one of the Cu—O distances is rather long [2.740 (2) ], almost at the limit of coordination. These Cu—O bonds define an equatorial plane to which the Cu—N bonds to the INA ligands are almost perpendicular, the Cu—N vectors subtending angles of 2.4 (1) and 2.3 (1)° to the normal to the plane. The metal coordination geometry can be described as a slightly distorted trigonal bipyramid if the extremely weak Cu—O bond is disregarded, or as a highly distorted square bipyramid if it is not. The double acetate bridge between the copper ions is not coplanar with the CuO4 equatorial planes, the dihedral angle between the (O—C—O)2 and O—Cu—O groups being 34.3 (1)°, resulting in a sofa-like conformation for the 8-member bridging loop. In the crystal, N—H...O hydrogen bonds occur, some of which generate a head-to tail-linkage between INA units, giving raise to chains along [101]; the remaining ones make inter-chain contacts, defining a three-dimensional network. There are in addition a number of C—H...O bonds involving aromatic H atoms. Probably due to steric hindrance, the aromatic rings are not involved in significant π...π interactions.
Crystal and molecular structure of bis(4-bromo-N-(diethylcarbamothioyl)benzamido)nickel(II) complex  [cached]
Gun Binzet,Ulrich Fl?rke,Nevzat Külcü,Hakan Arslan
European Journal of Chemistry , 2012, DOI: 10.5155/eurjchem.3.1.37-39.591
Abstract: We report the synthesis of bis(4-bromo-N-(diethylcarbamothioyl)benzamido)nickel(II) complex of an benzoylthiourea derivative formulated as C24H28Br2NiN4O2S2. The structure of compound has been determined by single-crystal X-ray diffraction analysis. It crystallizes in the monoclinic space group, P21/c with unit cell dimensions of a = 12.9099(17) , b = 15.264(2) , c = 14.0287(19) , β = 92.140(4)o and V = 2762.5(6) 3. In this compound, the nickel atom is coordinated by two sulphur and two oxygen atoms from two 4-bromo-N-(diethylcarbamothioyl)benzamide molecules forming an distorted square-planar geometry.
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