Journal articles: 'Nickel complexe'

1

Liu, Xuan Wen, Xi Wi Qi, and Feng Liu. "Synthesis, Structures, Properties and DFT Studies of a New Bicopper Complexe [Cu(Hdmg)₄(Hdmg)(teda)]·6H₂O." Applied Mechanics and Materials 470 (December 2013): 104–7. http://dx.doi.org/10.4028/www.scientific.net/amm.470.104.

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A new copper complexe [Cu (Hdmg)4(teda)]6H2O(H2dmg=dimethyl glyoxime;teda=triethylenediamine) was synthesized by solution method of nickel nitrate with corresponding ligands. Single crystal X-ray diffraction analysis reveals that crystal belongs to monoclinic, space group C2/c. The Cu2+ is five-coordinated with five N atoms of two dmg molecules and one teda molecule. The pdc anions, as a bridging ligand, link two adjacent Cu ions, forming a dinuclear structure. The structures and properties of complexes have been characterized by elemental analysis and IR spectrum. We also studied the electronic structure and orbital energies of the title complex by DFT methods, and the results reveals that the energy gap between LUMO and HOMO is disappeared. CCDC: 952374

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Masotti, H., G. Peiffer, Ch Siv, R. Valls, and R. Faure. "Cyclodimérisation Asymétrique du Penta-2,4-Dienoate de Méthyle Activée Par Un Complexe du Nickel." Bulletin des Sociétés Chimiques Belges 102, no. 7 (September 1, 2010): 461–65. http://dx.doi.org/10.1002/bscb.19931020705.

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3

Julien-Pouzol, M., S. Jaulmes, P. Laruelle, S. Carvalho, and E. D. Paniago. "Structure d'un complexe du nickel(II) avec l'aminoacétohydroxamate monosodique, Na[Ni(C2H4N2O2)(C2H5N2O2)].3H2O." Acta Crystallographica Section C Crystal Structure Communications 41, no. 5 (May 15, 1985): 712–15. http://dx.doi.org/10.1107/s0108270185005224.

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4

Siove, A., D. Ades, C. Chevrot, and G. Froyer. "Polymérisation électroinduite du 3,6 dibromo N-éthylcarbazole catalysée par un complexe du nickel zéro-valent." Journal de Chimie Physique 86 (1989): 155–61. http://dx.doi.org/10.1051/jcp/1989860155.

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5

Cheng, Xue Hua, Xiu Lan Xin, Li Hua Yin, and Yang Yu. "Syntheses and Spectral Properties of Tetra-(4,4-Dimethyl-Phenyl) Dithiolene Nickel Complex." Applied Mechanics and Materials 469 (November 2013): 81–86. http://dx.doi.org/10.4028/www.scientific.net/amm.469.81.

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Tetra-(4,4-dimethyl-phenyl) dithiolene nickel complex was synthesized by sulfuration with P2S5 and nickel complexs using bis-(4,4-dimethyl-phenyl) ethanedione as raw material. The structure of dithiolene nickel complexes was characterized by melting point, IR and 1HNMR. The maximum absorption spectra of this dithiolene nickel complexes in different solvent was measured by Ultraviolet-Visible-near Infrared Spectrum, and the photo stability and thermal stability were discussed. The results showed that this new method was used to synthesis bis-(4,4-dimethyl-phenyl) ethanedione, which greatly reduces the synthesis time compared to previous methods.

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6

Safavi, A., and L. Fotouhi. "Electrochemical reduction of nickel(II) dithiocarboxylates at the mercury electrode." Canadian Journal of Chemistry 75, no. 7 (July 1, 1997): 1023–29. http://dx.doi.org/10.1139/v97-122.

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The reduction mechanisms of a series of nickel(II) dithiocarboxylate complexes have been investigated in dimethyl sulphoxide at the mercury electrode. Various electrochemical techniques, including polarography, cyclic voltammetry, chronoamperometry, and controlled potential coulometry, were employed. The reduction of the complexes of the acid derivatives of 2-aminocyclopentene-1-dithiocarboxylate (ACD) proceeds initially by an ECE mechanism (electron transfer – chemical reaction – electron transfer) followed by a one-electron irreversible process. The nature of the complete electrode reaction suggests a metal-centered reduction. The nickel complexes of the ester derivatives of ACD underwent a one-electron reduction that was subject to a follow-up catalytic reaction (EC′ mechanism) and the original complex is regenerated through this regeneration reaction. Keywords: reduction, nickel(II) dithiocarboxylate, mercury electrode.

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7

Rayabarapu, Dinesh Kumar, and Chien-Hong Cheng. "Novel cyclization and reductive coupling of bicyclic olefins with alkyl propiolates catalyzed by nickel complexes." Pure and Applied Chemistry 74, no. 1 (January 1, 2002): 69–75. http://dx.doi.org/10.1351/pac200274010069.

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In this article, new metal-mediated cyclization and reductive coupling reactions of bicyclic olefins with alkynes are described. Oxabicyclic alkenes undergo cyclization with alkyl propiolates at 80 C catalyzed by nickel complexes to give benzocoumarin derivatives in high yields. The reaction of bicyclic alkenes (oxa- and azacyclic alkenes) with alkyl propiolates at room temperature in the presence of the same nickel complex gave 1,2-dihydro-napthelene derivatives in good-to-excellent yields. This reductive coupling reaction proceeds under very mild conditions in complete regio- and stereoselective fashion. A mechanism to account for the coumarin formation and the reductive coupling is proposed.

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8

Zhang, Jie, Jiarui Chang, Ting Liu, Bula Cao, Yazhou Ding, and Xuenian Chen. "Application of POCOP Pincer Nickel Complexes to the Catalytic Hydroboration of Carbon Dioxide." Catalysts 8, no. 11 (November 1, 2018): 508. http://dx.doi.org/10.3390/catal8110508.

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The reduction of CO2 is of great importance. In this paper, different types of bis(phosphinite) (POCOP) pincer nickel complexes, [2,6-(R2PO)2C6H3]NiX (R = tBu, iPr, Ph; X = SH, N3, NCS), were applied to the catalytic hydroboration of CO2 with catecholborane (HBcat). It was found that pincer complexes with tBu2P or iPr2P phosphine arms are active catalysts for this reaction in which CO2 was successfully reduced to a methanol derivative (CH3OBcat) with a maximum turnover frequency of 1908 h−1 at room temperature under an atmospheric pressure of CO2. However, complexes with phenyl-substituted phosphine arms failed to catalyze this reaction—the catalysts decomposed under the catalytic conditions. Complexes with iPr2P phosphine arms are more active catalysts compared with the corresponding complexes with tBu2P phosphine arms. For complexes with the same phosphine arms, the catalytic activity follows the series of mercapto complex (X = SH) ≈ azido complex (X = N3) >> isothiocyanato complex (X = NCS). It is believed that all of these catalytic active complexes are catalyst precursors which generate the nickel hydride complex [2,6-(R2PO)2C6H3]NiH in situ, and the nickel hydride complex is the active species to catalyze this reaction.

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9

Lehmkuhl, Herbert, Johannes Elsäßer, Reinhard Benn, Barbara Gabor, Anna Rufińska, Richard Goddard, and Carl Krüger. "Ein-und zweikernige Phosphorinylnickel-Komplexe/Mono-and Binuclear Phosphorinylnickel Complexes." Zeitschrift für Naturforschung B 40, no. 2 (February 1, 1985): 171–81. http://dx.doi.org/10.1515/znb-1985-0206.

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AbstractThe ethylene molecule in the binuclear complex [bis(2-4η-phosphorinyl)nickel](η2 -ethylene)-P,P′-nickel (1) is displaced by 1-alkenes in an equilibration reaction to give the corresponding (η2 -1-alkene)nickel complexes 2-5. The NMR spectra of the octene complex 3 and the propene complex 6 are temperature dependent because of valence isomerization in the phosphorinyl group and rotation of the olefin. The binuclear structure is not maintained upon displacement of the ethylene by butadiene or isoprene. One nickel atom is displaced as the dodecatrienediylnickel complex 9 and the remaining bis(phosphorinyl)nickel fragment B reacts with insertion of the diene into one allyl-Ni bond to give 7 resp. 8. The molecular structure of 7 was determined by X-ray crystallography.

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10

Lukeš, Ivan, Zdeněk Kváča, and Ivor Dominák. "Complexes of N-methyliminobis(methylenephosphonic) acid with cobalt, nickel, copper, and zinc." Collection of Czechoslovak Chemical Communications 53, no. 5 (1988): 987–94. http://dx.doi.org/10.1135/cccc19880987.

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The 1 : 1 cobalt, nickel, copper and zinc complexes of N-methyliminobis(methylenephosphonic) acid, and 1 : 2 cobalt and nickel complexes were prepared. The effect of alkali and alkali earth metals as "external cations" on the crystallization and stoichiometry of solid cobalt complex was investigated. Infrared and electronic spectra and magnetic susceptibilities indicate that cobalt and nickel form high-spin complexes. The coordination sphere of the central atom is formed by a distorted octahedron of the ligand oxygen atoms.

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11

Sugiyarto, KH, DC Craig, AD Rae, and HA Goodwin. "Structural and Electronic Properties of Iron(II) and Nickel(II) Complexes of 2,6-Bis(triazol-3-yl)pyridines." Australian Journal of Chemistry 46, no. 8 (1993): 1269. http://dx.doi.org/10.1071/ch9931269.

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Iron(II) and nickel(II) bis ( ligand ) complexes of 2,6-bis(1,2,4-triazol-3-yl)pyridine and the substituted derivatives 2,6-bis(1(N)-methyl-1,2,4-triazol-3-yl)pyridine 2,6-bis(5-methyl-1,2,4-triazol-3-yl)pyridine and 2,6-bis(1,5-dimethyl-1,2,4-triazol-3-yl)pyridine have been prepared. Coordination of the unsubstituted ligand through N4 of the triazolyl moieties is confirmed by structure determination of [FeL2][NO3]2.4H2O and [NiL2]Cl2.3H2O. In both of these complex salts there is an extensive hydrogen-bonded network involving the N 1-H group, the anions and the water molecules. Bis [2,6-bis(1,2,4-triazol-3-yl)pyridine]nickel(II) dichloride trihydrate : monoclinic, space group C2/c, a 17.971(5), b 11.433(1), c 14.849(5) Ǻ, β 122.20(1)°, Z 4. Bis [2,6-bis(1,2,4-triazol-3-yl)pyridine]iron(II) dinitrate tetrahydrate : tetragonal, space group 141/a, a 11.488(2), c 21.055(7) Ǻ, Z 4. [FeL2]Cl2.3H2O is isostructural with the nickel complex and is high-spin but undergoes a partial transition to low-spin at low temperature. Conversion to low-spin is complete when the complex is dehydrated, and this change is associated with the effects of the hydrogen bonding. The solid iron complexes of the N-methyl-substituted ligands in which the hydrogen-bonding potential is reduced are entirely high-spin down to 77K. The complex of the 5-methyl derivative undergoes a continuous singlet ↔ quintet transition below room temperature.

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12

Petriček, Saša. "Structural Diversity of Nickel and Manganese Chloride Complexes with Pyridin-2-One." Molecules 25, no. 4 (February 14, 2020): 846. http://dx.doi.org/10.3390/molecules25040846.

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Reactions of NiCl2·6H2O and pyridin-2-one (C5H5NO = Hhp) afforded novel molecular complexes, i.e., mononuclear [NiCl2(Hhp)4] (1), dinuclear [NiCl2(Hhp)(H2O)2]2.2Hhp (3) and [Ni2Cl4(Hhp)5]·2MeCN (4), and an ionic complex [Ni(Hhp)6]Cl2 (2). Single-crystal X-ray analyses revealed two modes of Hhp ligation in these complexes: a monodentate coordination of carbonyl oxygen in all of them and an additional µ2-oxygen bridging coordination in the dinuclear complex 4. Three bridging molecules of Hhp span two nickel(II) ions in 4 with a 2.9802 (5) Å separation of the metal ions. Complex 3 is a chlorido-bridged nickel dimer with a planar Ni2(µ-Cl)2 framework. Hydrogen bonds and parallel stacking arrangements of the Hhp molecules govern the connectivity patterns in the crystals, resulting in 1D structures in 1 and 5 or 2D in 3. A single manganese compound [MnCl2(Hhp)4] (5), isostructural to 1, was isolated under the similar conditions. This is in contrast to four nickel(II) chloride complexes with Hhp. Thermal analyses proved the stability of complexes 1 and 3 in argon up to 145 °C and 100 °C, respectively. The decomposition of 1 and 3 yielded nickel in argon and nickel(II) oxide in air at 800 °C.

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13

Joshi, Seema, M. M. Husain, Ramesh Chandra, S. K. Hasan, and R. C. Srivastava. "Hydroxyl radical formation resulting from the interaction of nickel complexes of L-histidine, glutathione or L-cysteine and hydrogen peroxide." Human & Experimental Toxicology 24, no. 1 (January 2005): 13–17. http://dx.doi.org/10.1191/0960327105ht493oa.

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L-histidine, L-cysteine, reduced glutathione (GSH) and other bioligands, which are ubiquitously present in biological systems, are recognized as antioxidants. Studies have shown that nickel (II) complexed with these ligands catalyzes the disproportionation of H2O2, leading to the generation of hydroxyl radicals (OH•). However, none of the studies could provide information regarding effective concentrations at which these ligands act either as pro-oxidant or antioxidant. Therefore, the observed paradoxical behaviour of biological antioxidants in nickel-induced oxidative response was evaluated. Benzoic acid (BA) is hydroxylated by OH• radical to form highly fluorescent dihydroxy benzoate (OH-BA). We used this model to study the effect of nickel complexes of L-histidine, GSH or L-cysteine on the hydroxylation of BA. The concentration-dependent effect of L-histidine, GSH and L-cysteine, or nickel on the hydroxylation of BA was studied. The hydroxylation of BA was significantly enhanced up to 1:0.5 molar ratio (Ni:hist or GSH). However, beyond 1:0.5 molar ratios, histidine/GSH inhibited the hydroxylation and complete inhibition was observed at 1:1 molar ratios. Sorbitol and caffeic acid, considered as scavengers of hydroxyl radicals, inhibited nickel-induced hydroxylation of BA. The present study demonstrates paradoxical behaviour of these bioligands. They act as pro-oxidant at lower ligand ratios and as antioxidant at higher ligand ratios. The redox properties of nickel complexes with histidine, GSH or cysteine reported here may be crucial for the toxicity of nlckel.

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14

Ion, Ana, Florinel G. Banica, and Constantin Luca. "Electrochemical Investigations of the Nickel(II)-Penicillamine System. Inert and Labile Complexes Detected by Polarography." Collection of Czechoslovak Chemical Communications 63, no. 2 (1998): 187–98. http://dx.doi.org/10.1135/cccc19980187.

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The effect of penicillamine on nickel diffusion current demonstrates that Ni22- is a kinetically inert complex whereas NiL is labile (L2- = (CH3)2C(S-)CH(NH2)COO-)). The difference in kinetic stability between the analogous bis-ligand complexes of Ni(II) with either penicillamine or cysteine is tentatively explained taking into account their structures. It is suggested that nickel detoxication by chelate ligands depends on the inert character rather than on the thermodynamic stability of the relevant nickel complex.

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15

Panchenko, Tetiana, Maria Evseeva, and Anatoliy Ranskiy. "Copper(II) and Nickel(II) with N,N’-bis(salicylidene)thiosemicarbazide Heterometal Complex Compounds." Chemistry & Chemical Technology 8, no. 3 (September 1, 2014): 243–48. http://dx.doi.org/10.23939/chcht08.03.243.

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16

Krstic, Milena, Branka Petković, Miloš Milčić, Dušan Mišić, and Juan Francisco Santibanez. "Synthesis, characterization and biological study of new dinuclear zinc(II) and nickel(II) octaaza macrocyclic complexes." Macedonian Journal of Chemistry and Chemical Engineering 38, no. 1 (May 30, 2019): 1. http://dx.doi.org/10.20450/mjcce.2019.1599.

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Two new nitrato complexes of zinc and nickel with 1,4,8,11-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc), have been synthesized and characterized. The IR spectral peaks showed that the coordinated and ionic nitrate ions are in agreement with the formula proposed by elemental analysis. Conductometric titrations predicted methanol to be a convenient solvent for synthesis and revealed the stoichiometry of the complexes, while molar electrical conductivities indicated a 1 : 3 complex electrolyte type for the zinc complex, and a 1 : 2 complex electrolyte type for the nickel complex. The optimized complex structure was obtained by molecular modeling and density functional theory calculations. The biological activity of the novel complexes was examined by screening eight different bacterial strains and two cancer cell lines. The zinc complex showed better antimicrobial activity against the bacterial strains, while the complexes did not show significance antiproliferative activity toward cancer cells MCF-7 and MDA-MB-231.

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17

Chakrabarti, S., P. C. Mandal, and S. N. Bhattacharyya. "Reactions of Ni(II) and its complexes with free radicals derived from thymine." Canadian Journal of Chemistry 71, no. 3 (March 1, 1993): 307–12. http://dx.doi.org/10.1139/v93-045.

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The effects of nickel (II) ions and its complexes on the products arising from the γ-radiolysis of thymine were studied. The decomposition of the pyrimidine base and formation of different radiolytic products indicate that nickel(II) ions or its complexes have little effect on the radiosensitivity of thymine. The transient hydroxyl adduct of thymine reacts with Ni(II) with the formation of a complex having a nickel–carbon bond. The rate constants for the reactions are of the order of 106 dm3 mol−1 s−1. Possible mechanisms for the formation of different products in the radiolysis of thymine in the presence of nickel(II) compounds are discussed.

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18

Dedov, A. G., O. A. Slyakhtin, A. S. Loktev, G. N. Mazo, S. A. Malyshev, and I. I. Moiseev. "New metal-oxide composite materials as efficient catalysts of the partial oxidation of methane." Доклады Академии наук 484, no. 3 (April 15, 2019): 299–302. http://dx.doi.org/10.31857/s0869-56524843299-302.

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Single-phase complex oxides Nd2-yCayCoxNi1-xO4 have been synthesized for the first time. Composites prepared by the reduction of these compounds with hydrogen and containing Nd2O3, CaO, and cobalt and nickels metals have been used for the first time as catalysts of the partial oxidation of methane. The maximal methane conversions (97%) and syngas yields (96%) at 900 °С have been detected in the presence of the composite obtained from Nd1,5Ca0,5NiO4. At T < 850 °C, the nickel–cobalt composite synthesized from Nd1,3Ca0,7Co0,4Ni0,6O4 turned out to be more selective in the formation of syngas. Decreasing the partial oxidation temperature from 900 °С to 750 °С leads to the oxidation of metallic nickel and cobalt to oxides and to partial resynthesis of complex oxides with perovskite and K2NiF4 structures. The observed differences in temperature dependence of the catalytic properties of composites with various Ni/Co ratios can be associated with the participation of complex oxides in catalysis of the partial oxidation of methane at low temperatures.

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19

Aiyelabola, T. O., E. O. Akinkunmi, and O. Osungunna. "Syntheses, Characterization and Biological Activity of Coordination Compounds of Propanedioic Acid and its Mixed Ligand Complexes with N,N'-Dihydroxy-2,3-butanediimine." Asian Journal of Chemistry 33, no. 8 (2021): 1911–18. http://dx.doi.org/10.14233/ajchem.2021.23309.

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The coordination compounds of propanedioic acid with cobalt(II), nickel(II) and copper(II) ions were synthesized using metal:ligand 1:2. In addition to this, mixed ligand complexes using the same metal ions with propanedioic acid as the primary ligand and N,N'-dihydroxy-2,3-butanediimine as the secondary ligand were also synthesized using M:L1:L2 (1:1:1) where L1 = propanedioic acid, L2 = N,N'-dihydroxy-2,3-butanediimine and M = Cu(II), Ni(II) and Cu(II). The synthesized compounds were characterized using FTIR, UV-vis, magnetic susceptibility measurement and percentage metal composition. The ligand and its metal complexes were tested for their cytotoxic and antibacterial activities. Results indicated that a dimeric square planar geometry was assumed by the cobalt(II) and nickel(II) propanedioic acid complexes. Octahedral geometry was proposed for both cobalt(II) and copper(II) mixed ligand complexes. A dinuclear square pyramidal geometry was suggested for the copper(II) propanedioic acid complex and square planar/octahedral geometry for the nickel(II) mixed ligand complex. The copper(II) propanedioic acid complex elicited the best cytotoxic activity. On the other hand, the nickel(II) propanedioic acid complex showed the remarkable antimicrobial activity. The compounds exhibited good antimicrobial activity in most of the cases with the exception of the cobalt(II) propanedioic acid complex. It was concluded that coordination of the ligands to the metal ions lowered the toxicity of the ligands. It was further concluded that the antimicrobial activity of the compounds was partly dependent on the synergism/additive effect of the intrinsic therapeutic properties of the metal ion and the ligands within the coordination sphere of the complexes synthesized. And this is also in part a function of the geometry assumed by the complexes.

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20

Varasteanu, Dana, Irina Chican, Sanda Maria Doncea, Iuliana Raut, Mariana Calin, and Luiza Jecu. "Nickel (II) and Cobalt (II) Complexes of Some Amino Acid-based Surfactants with Antimicrobial Activity." Revista de Chimie 70, no. 2 (March 15, 2019): 361–64. http://dx.doi.org/10.37358/rc.19.2.6917.

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Nickel and cobalt complexes of lauroyl-glycine, lauroyl-glycylglycine and 1,12-dodecandioyl-diglycylglycine were synthesized. The FTIR spectroscopy confirmed the complex formation. The antimicrobial activity of synthesized nickel and cobalt complexes was investigated against several bacteria and fungi: Bacillus cereus, Pseudomonas aeruginosa, Candida albicans, and Aspergillus flavus. Generally, the nickel and cobalt complexes of the investigated surfactants showed no antimicrobial activity on Pseudomonas aeruginosa, a moderate one on Bacillus cereus and Aspergillus flavus. The most susceptible microorganism was Candida albicans, which is considered one of most common nosocomial infections. The results suggest the potential application of tested compounds as antimicrobial agents against targeted pathogens.

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21

Diao, Tianning, Qiao Lin, and Gregory Dawson. "Experimental Electrochemical Potentials of Nickel Complexes." Synlett 32, no. 16 (August 26, 2021): 1606–20. http://dx.doi.org/10.1055/s-0040-1719829.

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AbstractNickel-catalyzed cross-coupling and photoredox catalytic reactions has found widespread utilities in organic synthesis. Redox processes are key intermediate steps in many catalytic cycles. As a result, it is pertinent to measure and document the redox potentials of various nickel species as precatalysts, catalysts, and intermediates. The redox potentials of a transition-metal complex are governed by its oxidation state, ligand, and the solvent environment. This article tabulates experimentally measured redox potentials of nickel complexes supported on common ligands under various conditions. This review article serves as a versatile tool to help synthetic organic and organometallic chemists evaluate the feasibility and kinetics of redox events occurring at the nickel center, when designing catalytic reactions and preparing nickel complexes.1 Introduction1.1 Scope1.2 Measurement of Formal Redox Potentials1.3 Redox Potentials in Nonaqueous Solution2 Redox Potentials of Nickel Complexes2.1 Redox Potentials of (Phosphine)Ni Complexes2.2 Redox Potentials of (Nitrogen)Ni Complexes2.3 Redox Potentials of (NHC)Ni Complexes

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22

Abdullah, Iman, Riri Andriyanti, Dita Arifa Nurani, and Yuni Krisyuningsih Krisnandi. "Nickel-phenanthroline Complex Supported on Mesoporous Carbon as a Catalyst for Carboxylation under CO2 Atmosphere." Bulletin of Chemical Reaction Engineering & Catalysis 16, no. 1 (March 1, 2021): 111–19. http://dx.doi.org/10.9767/bcrec.16.1.9733.111-119.

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Carbon dioxide is a highly potential renewable C1 source for synthesis of fine chemicals. Utilization of CO2 in carboxylation reactions requires catalysts, such as: nickel complex for CO2 activation. However, the use of homogeneous catalysts in the reaction is still less efficient due to the difficulty of separating the product and catalyst from reaction mixture. Therefore, it is necessary to heterogenize the nickel complex in a solid support such as mesoporous carbon. In this report, mesoporous carbon (MC) prepared from phloroglucinol and formaldehyde through soft template method was used as a solid support for Ni-phenanthroline complex (Ni-phen). The catalyst was characterized by Fourier Transform Infra Red (FT-IR), X-Ray Diffraction (XRD), Scanning Electron Microscope - Energy Dispersive X-Ray (SEM-EDX), and Surface Area Analyzer (SAA). The result of SAA characterization showed that the pore diameter of MC was 6.7 nm and Ni-phen/MC was 5.1 nm which indicates that the materials have meso-size pores. Ni-phen/MC material was then used as a heterogeneous catalyst in the carboxylation reaction of phenylacetylene under an ambient CO2 pressure. The reactions were carried out in several variations of conditions such as temperature, time and catalyst types. Based on the results of the reaction, the best conditions were obtained at 25 °C for 8 h of reaction time using Ni-phen/MC catalyst. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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23

Arnold, Dennis P., Raymond C. Bott, Helen Eldridge, Fiona M. Elms, Graham Smith, and Mike Zojaji. "Functionalization of 5,15-Diphenylporphyrin: Preparation and X-Ray Crystal Structures of meso Nitro, Bromo, and Trimethylsilylethynyl Derivatives." Australian Journal of Chemistry 50, no. 5 (1997): 495. http://dx.doi.org/10.1071/c96193.

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Substitutions on 5,15-diphenylporphyrin led to the isolation of mono- and di-bromo and mono- and di-nitro derivatives, which were converted into their respective nickel(II) complexes. Reaction of the bromoporphyrins with iodine/silver nitrite resulted in nitrodebromination as well as conventional nitration. The nickel(II) complex of 5-nitro-10,20-diphenylporphyrin was reduced to the 5-amino derivative. The nickel(II) complexes of the bromoporphyrins were converted into the respective mono- and bis-(trimethylsilylethynyl) species. The crystal structures of 5-nitro-10,20-diphenylporphyrin, 5-bromo- 10,20-diphenylporphyrinatonickel(II), and 10,20-diphenyl-5-(trimethylsilylethynyl)porphyrinatonickel(II) were determined.

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24

Hall, Iris H., Merrill C. Miller, and Douglas X. West. "Antineoplastic and Cytotoxic Activities of Nickel(II) Complexes of Thiosemicarbazones." Metal-Based Drugs 4, no. 2 (January 1, 1997): 89–95. http://dx.doi.org/10.1155/mbd.1997.89.

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Nickel(II) complexes of thiosemicarbazons were observed to be potent cytotoxic agents in human and rodent tissue cultured tumor cells. Each compound demonstrated a slightly different profile in the various histological types of tumors. The nickel complex of Appip demonstrated the most potent in vivo activity in the Ehrlich ascites carcinoma. This agent selectively inhibited L1210 DNA and purine syntheses, and DNA polymerase α, PRPP-amido transferase, IMP-dehydrogenase, dihydrofolate reductase, TMP-kinase and thymidylate synthetase activities. L1210 DNA strand scission was evident and DNA viscosity was reduced after 24 hr incubation. The nickel complexes were not L1210 DNA topoisomerase II inhibitors.

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25

Bennett, Martin A. "Aryne Complexes of Zerovalent Metals of the Nickel Triad." Australian Journal of Chemistry 63, no. 7 (2010): 1066. http://dx.doi.org/10.1071/ch10198.

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The chemistry of dihapto-aryne complexes of the zerovalent Group 10 metals of general formula [M(η2-aryne)L2] (M = Ni, Pd, Pt; L = various tertiary phosphines) is reviewed, with emphasis on the highly reactive nickel(0) compounds (aryne = benzyne, C6H4; 4,5-difluorobenzyne, 4,5-C6H2F2; 2,3-naphthalyne, 2,3-C10H6; L2 = 2 PEt3, 2 PiPr3, 2 PCy3, dcpe). These can be generated by alkali metal reduction of the appropriate (2-halogenoaryl)nickel(ii) halide precursors, such as [NiX(2-XC6H4)L2], which in turn are accessible by oxidative addition of the 1,2-dihaloarene to nickel(0) precursors such as [Ni(1,5-COD)2]. The X-ray structure of [Ni(η2-C6H4)(dcpe)] shows that this compound is a typical 16-electron Ni(0) (3d10) species in which benzyne acts as a 2π-electron donor. Several unusual organonickel compounds derived from [Ni(η2-4,5-C6H2F2)(PEt3)2] have been isolated recently, including [Ni2(μ-η2:η2-4,5-C6H2F2)(PEt3)4], in which a 4π-electron donor 4,5-difluorobenzyne is located at right-angles to a pair of nickel atoms. Free benzyne can be intercepted by both [Ni(η2-C2H4)(dcpe)] and [Pt(η2-C2H4)(PPh3)2], but the resulting benzyne complexes rapidly insert benzyne to give the appropriate η1:η1-2,2′-biphenylyl complexes. [Pt(η2-C6H4)(PPh3)2] also undergoes rapid ortho-metallation to give [PtPh(2-C6H4PPh2)(PPh3)]. However, a trapping reaction has been used to make the first 1,4-benzdiyne complex, [{Ni(dcpe)2}2(μ-η2:η2-1,4-C6H2)] by treatment of the 4-fluorobenzyne complex [Ni(η2-4-FC6H3)(dcpe)] with LiTMP. The use of alkali metals in the preparation of the η2-benzyne complexes is avoided in a more recently developed procedure, which starts from (2-bromophenyl)boronic acid, and is based on Suzuki–Miyaura coupling. This procedure has made accessible for the first time an aryne complex of palladium(0), [Pd(η2-C6H4)(PCy3)2], and the labile nickel(0) complex [Ni(η2-C6H4)(PPh3)2]. The aryne-nickel(0) complexes Ni(η2-aryne)L2 (L2 = 2 PEt3, dcpe) undergo sequential insertions into the aryne-metal bond with unsaturated molecules, such as CO, C2F4, substituted alkynes, substituted diynes, alkynylphosphines, and alkynyl thioethers, often with considerable regioselectivity. After the reductive elimination of two nickel-carbon σ-bonds, a variety of interesting polycyclic compounds can be obtained.

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26

Matsubara, Fujii, Hosokawa, Inatomi, Yamada, and Koga. "Fluorine-Substituted Arylphosphine for an NHC-Ni(I) System, Air-Stable in a Solid State but Catalytically Active in Solution." Molecules 24, no. 18 (September 4, 2019): 3222. http://dx.doi.org/10.3390/molecules24183222.

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Monovalent NHC-nickel complexes bearing triarylphosphine, in which fluorine is incorporated onto the aryl groups, have been synthesized. Tris(3,5-di(trifluoromethyl)-phenyl)phosphine efficiently gave a monovalent nickel bromide complex, whose structure was determined by X-ray diffraction analysis for the first time. In the solid state, the Ni(I) complex was less susceptible to oxidation in air than the triphenylphosphine complex, indicating greatly improved solid-state stability. In contrast, the Ni(I) complex in solution can easily liberate the phosphine, high catalytic activity toward the Kumada–Tamao–Corriu coupling of aryl bromides.

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27

Li, Shen Xin, Wei Hu, Ying Wang, and Song Wu. "Hydrolysis of BNPP Catalyzed by the Dodecyliminodiacetate Nickel (II) Complexes." Advanced Materials Research 746 (August 2013): 123–27. http://dx.doi.org/10.4028/www.scientific.net/amr.746.123.

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One novel dodecyliminodiacetate nickel (II) complex were synthesized and characterized, and these complexes were used as mimic hydrolytic in catalytic hydrolysis of bis (p-nitrophenyl) phosphate (BNPP). The analysis of specific absorption spectra of the hydrolytic reaction systems indicated that the catalytic hydrolysis involved the key intermediates formed by BNPP with nickel (II) complexes. The kinetic parameter of BNPP catalytic hydrolysis has been calculated and the activation energy for the catalytic hydrolysis is 95.26kJ·mol-1.

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28

Eberhardt, Nathan A., and Hairong Guan. "Nickel Hydride Complexes." Chemical Reviews 116, no. 15 (July 20, 2016): 8373–426. http://dx.doi.org/10.1021/acs.chemrev.6b00259.

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29

Eremenko, I. L., S. E. Nefedov, A. A. Sidorov, and I. I. Moiseev. "Trimethylacetate nickel complexes." Russian Chemical Bulletin 48, no. 3 (March 1999): 405–16. http://dx.doi.org/10.1007/bf02496153.

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30

Mirzoev, M. Sh, D. I. Khushvakhtov, S. A. Safarov, I. Kh Mangutov, A. M. Olimov, and M. N. Schakirov. "Removal of Temporomandibular Joint Bone Ankylosis by Shape Memory Materials." KnE Materials Science 2, no. 1 (July 17, 2017): 374. http://dx.doi.org/10.18502/kms.v2i1.822.

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A special attention has been attracted by the method of endoprosthesis replacement of temporomandibular joint. This research is devoted to an increase of surgical treatment efficiency of temporomandibular joint bone ankylosis using porous titanium nickel endoprosthesises. The analysis of distant results of application of porous nickelid titanium endoprosthesises for replacement of mandibular condylar processes in patients with temporomandibular ankylosis affects, according to anatomical specifics of affected organ, allows to make conclusion on possibility of complete restoration of lost anatomical and functional specifics of dentomaxilla apparatus. Through correspondence of hysteresis behavior of lost organ and recipient tissues to hysteresis behavior of whole complex system of endoprosthesis, the connecting tissues from implant surrounding areas grow through porous structure of implant not causing any aggressive reactions from organism side.

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31

Al-Qahtani, Salhah D. "Solution and Solid State Study of Nickel(II) Ternary Complexes Containing 5-Aminolevulinic Acid Drug and Amino Acids." Asian Journal of Chemistry 32, no. 7 (2020): 1563–68. http://dx.doi.org/10.14233/ajchem.2020.22658.

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Solution equilibria of the systems Ni(II)-5-aminolevulinic acid as ligand (A) and the amino acids [alanine (Ala), valine (Val), methylamine (Met), imidazole (Imi), Histidine (His), serine (Ser), cysteine (Cys) and penicillamine (Pen)] as ligands (L) have been studied pH-metrically. The stability constants of mixed ligand complexes were calculated with I = 0.10 mol L-1 KNO3 using HYPERQUAD program at 25 ± 0.1 ºC. The log10 X values showed a higher stabilities for the mixed ligand complexes compared to the binary analogues. The synthesis and characterization of the new amino acid mononuclear Ni(II) binary complex [NiA] (1) and ternary complex [NiAL] (2) were achieved via molar conductance, elemental analysis UV-vis, IR, 1H NMR, thermal analysis and magnetic moment. The thermogravimetric analysis of complexes were investigated by TG-DTA suggests that the complexes possess high thermal stability formation and their respective nickel oxide for 1 and nickel sulfide for 2 as final chemical entities, which are thermally stable. The nickel(II) chelates were found to be non-electrolytes, diamagnetic moments and the geometry around Ni(II) ion in complexes 1 and 2 is square planar

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32

Anuja, K., K. Hussain Reddy, K. Srinivasulu, and D. Dhanalakshmi. "Synthesis, Structural Characterization and DNA Binding Studies on Transition Metal Complexes with 2-Formylpyridine Benzoylhydrazone." Asian Journal of Chemistry 32, no. 2 (December 30, 2019): 322–28. http://dx.doi.org/10.14233/ajchem.2020.22389.

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The hydrazone ligand, 2-formylpyridine benzoylhydrazone (FPBH) has been used to synthesize copper(II), nickel(II) and cobalt(II) complexes and characterized by elemental analyses, mass spectra, molar conductivity data IR, UV-visible spectroscopy. The complexes are found to have general formula M(FPBH)2 (where, M = Cu(II), Ni(II) and Co(II). Further the copper complex is investigated using ESR spectra. The spin Hamiltonian, orbital reduction and bonding parameters are calculated for the complex. The complex, Ni(FPBH)2 is structurally characterized based on single crystal X-ray crystallography. The complex crystallizes in monoclinic space group P21/c with a = 11.2632(2) Å, b = 8.8958(2) Å, c = 23.0834(5) Å, α = 90°, β = 90.858(2)°, γ = 90°, V = 2312.59(8) Å3 and Z = 4 with central Ni(II) ion in distorted octahedral structure coordinated by two tridentate FPBH ligand. The interactions of these complexes with calf thymus DNA have been investigated using absorption spectrophotometry. The copper complex binds more strongly than either nickel or cobalt complexes.

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33

Baker, Anthony T., and Jeremy P. Matthews. "Iron(II) and Nickel(II) Complexes of 6-(Pyrazol-1-yl)-2,2' -bipyridine." Australian Journal of Chemistry 52, no. 4 (1999): 339. http://dx.doi.org/10.1071/c99029.

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Iron(II) and nickel(II) complexes of 6-(pyrazol-1-yl)-2,2′-bipyridine (pzbpy) have been prepared and characterized by magnetic susceptibility measurements and electronic spectroscopy. The magnetic behaviour of the iron(II) complexes and the electronic spectra of the nickel(II) complex indicate that pzbpy is a relatively strong-field ligand though its field strength is not as high as that of 2,2′:6′,2″-terpyridine. Comparisons of the field strength of terimine and analogous ligands are presented.

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34

Türkel, Naciye. "Stability Constants of Mixed Ligand Complexes of Nickel(II) with Adenine and Some Amino Acids." Bioinorganic Chemistry and Applications 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/374782.

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Nickel is one of the essential trace elements found in biological systems. It is mostly found in nickel-based enzymes as an essential cofactor. It forms coordination complexes with amino acids within enzymes. Nickel is also present in nucleic acids, though its function in DNA or RNA is still not clearly understood. In this study, complex formation tendencies of Ni(II) with adenine and certain L-amino acids such as aspartic acid, glutamic acid, asparagine, leucine, phenylalanine, and tryptophan were investigated in an aqueous medium. Potentiometric equilibrium measurements showed that both binary and ternary complexes of Ni(II) form with adenine and the above-mentioned L-amino acids. Ternary complexes of Ni(II)-adenine-L-amino acids are formed by stepwise mechanisms. Relative stabilities of the ternary complexes are compared with those of the corresponding binary complexes in terms ofΔlog10⁡K,log10⁡X, and % RS values. It was shown that the most stable ternary complex is Ni(II):Ade:L-Asn while the weakest one is Ni(II):Ade:L-Phe in aqueous solution used in this research. In addition, results of this research clearly show that various binary and ternary type Ni(II) complexes are formed in different concentrations as a function of pH in aqueous solution.

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35

Müller, Christiane, Lutz Stamp, and Heindirk torn Dieck. "Synthese und Struktur von Monoazadienkomplexen des Nickels: Cinnamylidenanilin- bis(triphenylphosphin)nickel / Synthesis and Structure of Monoazadiene Complexes of Nickel: Cinnamylideneanilinebis( triphenylphosphine)nickel." Zeitschrift für Naturforschung B 41, no. 4 (April 1, 1986): 519–22. http://dx.doi.org/10.1515/znb-1986-0420.

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The ethylene ligand in (C2H4)Ni[P(C6H5)3]2 is substituted at -20 °C by cinnamylideneaniline C6H5N=CH-CH=CHC6H5 to yield a polymer-like intermediate. Extraction at room temperature with n-hexane gives solutions, from which the very sparingly soluble title com pound crystallizes after several days. Since numerous coordination m odes are possible for 1-m̱onoazadienes (MAD)RN=CH-CH=CHR', an X-ray structure analysis was performed, which showed an η2 (C=C )-coordinated MAD ligand. Although the ligand conform ation is almost s-trans, the significant deviation from planarity (24°) in the solid state is in agreem ent with the rather small proton coupling 3J(H2-H3)= 4.5 Hz in solution

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36

Omoregie, Helen Oluwatola. "Synthesis, Physicochemical Properties and Antimicrobial Activities of Nickel(II) Complexes of 4,4,4-Trifluoro-1-(2-Naphthyl)-1,3-Butanedione and Their Adducts." International Journal of Chemistry 10, no. 4 (October 21, 2018): 1. http://dx.doi.org/10.5539/ijc.v10n4p1.

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Nickel(II) complex of 4,4,4-trifluoro-1-(2-Naphthyl)-1,3-butanedione(tfnb) and its 2,2′-bipyridine (bipy), ethylenediamine (en) and 1,10-phenanthroline (phen) adducts were synthesized and characterized by elemental analysis, infrared, electronic spectral, magnetic susceptibility measurements and antimicrobial activities. Three other nickel(II) compounds were synthesized along with these compounds. The bands in the 1651-1513 cm-1 have been assigned as ν(C=O) + ν(C=C). The infrared and electronic spectral measurements are indicative of a probable six-coordinate octahedral geometry for all the nickel(II) complexes and adducts. The antimicrobial activity shows that [Ni(tfnb)2]2H2O complex and its adducts have no antibacterial and antifungal activities.

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37

Rettenmeier, Christoph A., Hubert Wadepohl, and Lutz H. Gade. "Electronic structure and reactivity of nickel(i) pincer complexes: their aerobic transformation to peroxo species and site selective C–H oxygenation." Chemical Science 7, no. 6 (2016): 3533–42. http://dx.doi.org/10.1039/c5sc04644k.

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38

Sitzmann, Helmut, and Gotthelf Wolmershäuser. "Metallorganische Synthesen mit freien Cyclopentadienyl-Radikalen, I. Zweikernige Carbonylnickel-Komplexe mit mehrfach alkylierten Cyclopentadienyl-Liganden / Metalorganic Syntheses with Free Cyclopentadienyl Radicals, I. Dinuclear Carbonyl Nickel Complexes with Alkylated Cyclopentadienyl Ligands." Zeitschrift für Naturforschung B 50, no. 5 (May 1, 1995): 750–56. http://dx.doi.org/10.1515/znb-1995-0511.

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Abstract Cyclopentadienyl nickel complexes [(C5H2tBu3-1,2,4)Ni(M-CO)]2 (1) and [(C5HiPr4)Ni(μ-CO)]2 (2) have been synthesized from nickel tetracarbonyl and the corresponding lithium cyclopentadienide, and [(C5iPr5)Ni(μ-CO)]2 (3) has been obtained in high yield from nickel tetracarbonyl and the free pentaisopropylcyclopentadienyl radical. The crystal structure of 1 shows a complex on a crystallographic mirror plane with a bent Ni-C-Ni-C core whereas the crystal structure of 2 exhibits two independent planar molecules possessing crystallographic inversion symmetry.

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39

MacDermott, TE. "Synthesis of Some Novel Dinuclear Metal Complexes, Containing Both Square-Planar and Tetrahedral Metal Ions, by the Reactions of Coordinated Diamines with an α-Hydroxy Ketone." Australian Journal of Chemistry 38, no. 9 (1985): 1319. http://dx.doi.org/10.1071/ch9851319.

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Reactions between tris (propane-1,3-diamine)nickel(II) salts and 3- hydroxy-3-methylbutan-2-one in the presence of zinc(II) or cadmium(II) halides yield a series of di -oxygen-bridged dinuclear products which contain the square-planar nickel(II) complex of a 12-membered ligand ring one of whose members is either a zinc(II) or cadmium(II) halide. These complexes are thermally very stable but may be hydrolysed by water to give a complex of the corresponding α- imino alcohol.

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40

Buchspies, Jonathan, Md Mahbubur Rahman, and Michal Szostak. "Suzuki–Miyaura Cross-Coupling of Amides Using Well-Defined, Air- and Moisture-Stable Nickel/NHC (NHC = N-Heterocyclic Carbene) Complexes." Catalysts 10, no. 4 (March 31, 2020): 372. http://dx.doi.org/10.3390/catal10040372.

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In this Special Issue on N-Heterocyclic Carbenes and Their Complexes in Catalysis, we report the first example of Suzuki–Miyaura cross-coupling of amides catalyzed by well-defined, air- and moisture-stable nickel/NHC (NHC = N-heterocyclic carbene) complexes. The selective amide bond N–C(O) activation is achieved by half-sandwich, cyclopentadienyl [CpNi(NHC)Cl] complexes. The following order of reactivity of NHC ligands has been found: IPr > IMes > IPaul ≈ IPr*. Both the neutral and the cationic complexes are efficient catalysts for the Suzuki–Miyaura cross-coupling of amides. Kinetic studies demonstrate that the reactions are complete in < 1 h at 80 °C. Complete selectivity for the cleavage of exocyclic N-acyl bond has been observed under the experimental conditions. Given the utility of nickel catalysis in activating unreactive bonds, we believe that well-defined and bench-stable [CpNi(NHC)Cl] complexes will find broad application in amide bond and related cross-couplings of bench-stable acyl-electrophiles.

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41

Hoffmann, Florian, Uwe Böhme, and Gerhard Roewer. "Structure and Reactivity of (η5-Cyclopentadienyl)(triphenylphosphine)- (undecamethylcyclohexasilyl)nickel(II)-Hexane (2/1) Structure and Reactivity of (η5-Cyclopentadienyl)(triphenylphosphine)- (undecamethylcyclohexasilyl)nickel(II)-Hexane (2/1)." Zeitschrift für Naturforschung B 64, no. 11-12 (December 1, 2009): 1423–28. http://dx.doi.org/10.1515/znb-2009-11-1224.

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The nickel cyclohexasilyl complex CpNi(PPh3)Si6Me11 was synthesized from nickelocene, triphenylphosphine, and undecamethylcyclohexasilyl potassium and was fully characterized. It shows a relationship between its Si-Si bond lengths and its reactivity towards oxygen. The cleavage of one cyclopentadienyl ligand from nickelocene by silyl anions in the presence of additional ligands opens a promising new pathway to nickel silyl complexes of the type CpNi(L)-SiR3

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42

Bertini, Simone, and Martin Albrecht. "O-Functionalised NHC Ligands for Efficient Nickel-catalysed C–O Hydrosilylation." CHIMIA International Journal for Chemistry 74, no. 6 (June 24, 2020): 483–88. http://dx.doi.org/10.2533/chimia.2020.483.

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A series of C,O-bidentate chelating mesoionic carbene nickel(ii) complexes [Ni(NHC^PhO)2] (NHC = imidazolylidene or triazolylidene) were applied for hydrosilylation of carbonyl groups. The catalytic system is selective towards aldehyde reduction and tolerant to electron-donating and -withdrawing group substituents. Stoichiometric experiments in the presence of different silanes lends support to a metal–ligand cooperative activation of the Si–H bond. Catalytic performance of the nickel complexes is dependent on the triazolylidene substituents. Butyl-substituted triazolylidene ligands impart turnover numbers up to 7,400 and turnover frequencies of almost 30,000 h-1, identifying this complex as one of the best-performing nickel catalysts for hydrosilylation and demonstrating the outstanding potential of O-functionalised NHC ligands in combination with first-row transition metals.

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43

Ikram, Muhammad, Sadia Rehman, Fazle Subhan, Muhammad Nadeem Akhtar, and Mutasem Omar Sinnokrot. "Synthesis, characterization, thermal degradation and urease inhibitory studies of the new hydrazide based Schiff base ligand 2-(2-hydroxyphenyl)-3-{[(E)-(2-hydroxyphenyl)methylidene]amino}-2,3-dihydroquinazolin-4(1H)-one." Open Chemistry 15, no. 1 (December 29, 2017): 308–19. http://dx.doi.org/10.1515/chem-2017-0035.

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AbstractThe novel Schiff base ligand 2-(2-hydroxyphenyl)-3-{[(E)-(2-hydroxyphenyl)methylidene]amino}-2,3-dihydroquinazolin-4(1H)-one (H-HHAQ) derived from 2-aminobenzhydrazide was synthesized and characterized by elemental analyses, ES+-MS, 1H and 13C{1H}-NMR, and IR studies. The characterization of the ligand was further confirmed by single crystal analysis. The Schiff base ligand was complexed with metal ions like Co(II), Ni(II), Cu(II) and Zn(II) to obtain the bis-octahedral complexes. The ligand and its metal complexes were also studied for their urease inhibitory activities. All the tested compounds show medium to moderate activities for the enzyme, whereas the copper based complex was found to be much more active against urease with an IC50= 0.3 ± 0.1 μM±SEM, which is even more potent than the standard thiourea. The IC50 of the cobalt complex was 43.4±1.2 μM±SEM, whereas that of the nickel complex was 294.2±5.0 μM±SEM. The ligand H-HHAQ and the zinc complex were inactive against the tested enzyme.

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44

Čermák, Jan, Magdalena Kvíčalová, and Vratislav Blechta. "Nickel(0) and Palladium(0) Complexes with 1,3,5-Triaza-7-phosphaadamantane. Catalysis of Buta-1,3-diene Oligomerization or Telomerization in an AqueousBiphasic System." Collection of Czechoslovak Chemical Communications 62, no. 2 (1997): 355–63. http://dx.doi.org/10.1135/cccc19970355.

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New homoleptic nickel(0) and palladium(0) complexes with a water-soluble ligand, 1,3,5-triaza-7-phosphaadamantane, were prepared and characterized by 1H, 13C, and 31P NMR spectra. The complexes, together with the known analogous Ni(0) and Pd(0) complexes with tris(hydroxymethyl)phosphine, were found to be catalysts for buta-1,3-diene oligomerization or telomerization with water in an aqueous biphasic system without a cosolvent or a modifier. Tetrakis[tris(hydroxymethyl)phosphine]nickel (7) preferentially catalyzes oligomerization (both linear and cyclic) in the first example of a nickel-catalyzed buta-1,3-diene oligomerization in an aqueous biphasic system. Palladium complexes give telomers or linear oligomers in quantitative yields. In the case of the triazaphosphaadamantane complex 4, high selectivity to octadienyl ethers (87%) was observed. High values of metal leaching into the product phase in these reactions suggest an easy extraction of starting or intermediate metal complexes caused by the fact that both monomer and products are good ligands for the metal complexes in this particular case.

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45

Djer, Mulyadi M., and Bambang Madiyono. "Blood nickel level and its toxic effect after transcatheter closure of persistent duct arteriosus using Amplatzer duct occluder." Paediatrica Indonesiana 49, no. 1 (March 1, 2009): 33. http://dx.doi.org/10.14238/pi49.1.2009.33-8.

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Background Transcatheter closure using amplatzer duct occluder(ADO) is currently the treatment of choice for patent ductusarteriosus (PDA). The ADO device is constructed from a Nitinolwire mesh containing 55% nickel. Up to now, there is still acontroversy about the effects of nickel contained in ADO.Objectives To determine blood nickel level at six months aftertranscatheter closure of PDA using ADO, toxic effects of nickelat six months after PDA closure using ADO, and the effects ofnickel on complete blood count (CBC), blood glucose and renalfunction.Methods Subjects were patients with PDA at IntegratedCardiovascular Services, Dr. Cipto Mangunkusumo Hospital,Jakarta. Routine blood test and blood nickel levels were measuredat the time of the procedure, and at the end of the first, third, andsixth months after intervention.Results There were 29 patients who underwent heart catheteri-zation and PDA closure using ADO. A time series analysis wasconducted on 23 patients who completed six-month follow-upafter the intervention. Median blood nickel level before procedurewas 58 ng/mL while at one, three and six months afterwards were60, 63 and 64 ng/mL respectively. The blood nickel levels didnot differ significantly between pre- and post-ADO. After PDAclosure, no toxic effects of nickel were found, both clinically andlaboratorically.Conclusions PDA closure using ADO has no effects on the nickellevels, CBC, blood glucose and renal function;

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Groux, Laurent F., Francine Bélanger-Gariépy, and Davit Zargarian. "Phosphino-indenyl complexes of nickel(II)." Canadian Journal of Chemistry 83, no. 6-7 (June 1, 2005): 634–39. http://dx.doi.org/10.1139/v05-079.

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The BH3-protected phosphinoindenyl ligand indenyl(CH2)2PPh2·BH3 was used in the preparation of (η5/3:η0-indenyl(CH2)2PPh2·BH3)Ni(PPh3)Cl, which has been characterized by NMR spectroscopy and X-ray diffraction studies. On the other hand, all attempts at preparing the closely related complex (η5/3:η1-indenyl(CH2)2PPh2)NiCl, in which the tethered phosphine moiety is coordinated to the Ni centre, were unsuccessful. One of these unsuccessful attempts yielded instead the novel indenyl-PCP pincer complex {κP,κC,κP-1,3-(CH2CH2PPh2)2-2-indenyl}NiCl, which has been characterized by X-ray diffraction studies.Key words: indenyl complexes, tethered phosphines, PCP pincer complexes.

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47

Im, Ji Un, Chan Yong Yu, Jeong Yi Yoo, Se Mo Son, Gun Dae Lee, and Seong Soo Park. "A Study for Microwave Enhanced Synthesis of NIR Absorbing Materials." Materials Science Forum 510-511 (March 2006): 702–5. http://dx.doi.org/10.4028/www.scientific.net/msf.510-511.702.

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Symmetrically and unsymmerically substituted bis-dithiobenzil nickel complexes containing four substituted and unsubstituted methoxy groups were synthesized from a benzoin compound using phosphorous pentasulfide under the conventional thermal and microwave processing. The efficiency of microwave synthesis over the conventional thermal synthesis was illustrated by the yield of bisdithiobenzil nickel complex dyes. The samples were characterized by the means of elemental analyzer, 1HNMR, IR spectroscopy, Uv-vis spectroscopy and DSC.

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48

Bernhardt, PV, LS Curtis, NF Curtis, GA Lawrance, BW Skelton, and AH White. "Condensations of Ethane-1,2-Diamine, Formaldehyde and Ammonia (or Nitroethane) Directed by Nickel(II) or Copper(II). Crystal Structure of (8-Methyl-8-nitro-1,3,6,10,13,15-hexaazatricyclo[13.1.1.1 13,15]octadecane)nickel(II) Perchlorate." Australian Journal of Chemistry 42, no. 6 (1989): 797. http://dx.doi.org/10.1071/ch9890797.

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Both nickel(II) and copper(II) complexes of the sterically hindered linear tetraamines 1,3,5,7-tetra-azabicyclo [3.3.l]nonane-3,7-bis( ethanamine (4) and 3,3′-(ethane-1,2-diyl)bis(1,3,5,7-tetraaza-bicyclo [3.3.1] nonane (7) have been prepared from reaction of ethane-1,2-diamine complexes with formaldehyde and ammonia or by reaction of the metal salt with the quaternary 'hexamminium' cation (8) and ammonia, respectively. Spectroscopic properties and kinetics of the acid hydrolyses of these complexes are reported. Observed pseudo-first-order rate constants are of the order of 10-1 s-1 at 25° in 1 mol dm-3 HCl/NaCl; acid dependencies are reported. In addition to (4), a further acid-stable and presumably macrocyclic compound could be produced from reaction of [cu(en)2]2+ with formaldehyde and ammonia, assigned tentatively as (9). Further reaction of the nickel(II) complex of (4) with formaldehyde and nitroethane yielded the macrocyclic complex of (10), which was characterized by a crystal structure analysis. Reduction with zinc amalgam yielded an amine-substituted macrocyclic complex from the nitro-substituted precursor. The title complex [Ni(10)](ClO4)2.H2O crystallized in the space group P21/n, a 14.367(2), b 13.099(2), c 12.325(3) � , β 101.01(1)�. The nickel(II) was located in a square plane of two secondary (Ni-N 1.92 � ) and two tertiary nitrogens (Ni-N 1.93 � ); the 'football' formed as one cap from ammonia and formaldehyde condensation was clearly defined.

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Aliyev, S. G., R. A. Ismailova, Sh A. Ibrahimova, Z. G. Asgerova, and A. Z. Zalov. "RESEARCH INTO COMPLEX FORMATION OF COBALT(II) AND NICKEL (II) WITH 2-HYDROXY-5-NITROTHIOPHENOL AND DIPHENYLGUANIDINE." Chemical Problems 16, no. 2 (2018): 196–204. http://dx.doi.org/10.32737/2221-8688-2018-2-196-204.

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50

Templeton, D. M., and B. Sarkar. "Peptide and carbohydrate complexes of nickel in human kidney." Biochemical Journal 230, no. 1 (August 15, 1985): 35–42. http://dx.doi.org/10.1042/bj2300035.

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Abstract:

The predominant renal and urinary forms of nickel consist of low-Mr complexes. Similarities in the nature of these complexes have been found in kidneys of rats exposed parenterally to NiCl2 and in rat kidneys treated with NiCl2 in vitro. Similar complexes have also been identified after treatment of bovine and human renal soluble fractions with NiCl2. The bulk of nickel in all cases is associated with sulphated oligosaccharide fractions containing uronic acids and neutral sugars. This binding is non-specific, and nickel is readily displaced from these fractions by copper. Smaller amounts of nickel are bound to an acidic peptide, which was purified from human kidneys and partially characterized. Nickel was not displaced from this material by copper at physiological pH. These nickel complexes have not been found in plasma, suggesting that ligand exchange occurs during or after glomerular filtration of the metal.

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Journal articles on the topic 'Nickel complexe'

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