A Diazabutadiene stabilized Nickel(0) Cyclooctadiene Complex: Synthesis,Characterization and the Reaction with Diphenylacetylene

The reaction of [Ni(COD)₂] with one equivalent of DAB^Mes (DAB^Mes = (2,4,6‐Me₃C₆H₂)N=C(Me)‐C(Me)=N(2,4,6‐Me₃C₆H₂)) affords a mixture of the compound [Ni(DAB^Mes)₂] ( 2 ) and starting material [Ni(COD)₂]. The crystallographically characterized, diamagnetic complex 2 can be obtained in a stoichiometric reaction of [Ni(COD)₂] and two equivalents of DAB^Mes. This reaction can be accelerated by addition of 1‐chloro‐fluorobenzene or methyl iodide. In the presence of 1‐chloro‐fluorobenzene, [Ni(DAB^Mes)(COD)] ( 3 ) is available via reaction of [Ni(COD)₂] and one equivalent of DAB^Mes. The crystallographically characterized complex 3 reacts with diphenylacetylene to afford [Ni(DAB^Mes)(Ph‐C≡C‐Ph)] ( 4 ). A long‐wavelength absorption band in the UV‐Vis spectrum of this compound has to be assigned to a mixed MLCT/LL′CT transition, as quantum chemical calculations reveal.     

Bis­[methyl­enebis­(di­phenyl­phosphine)‐P,P′]­nickel(II) diperchlorate

The title compound, [Ni(Ph₂PCH₂PPh₂)₂](ClO₄)₂, was synthesized and its structure determined crystallographically. The Ni atom lies on an inversion centre and is at the center of a square formed by four P atoms which are necessarily coplanar. The Ni—P distances are 2.2188 (5) and 2.2322 (5) Å, and the P—Ni—P angle is 73.12 (3)°. The unique perchlorate anion is not coordinated to the Ni atom.     

Bis­(acetato‐O)­tetrakis­(imidazole‐N3)­nickel(II)

In the title compound, [Ni(C₂H₃O)₂(C₃H₄N₂)₄], the Ni atom is coordinated centrosymmetrically by four N and two O atoms in an octahedral coordination [Ni—N = 1.986 (3) and 2.054 (3) Å; Ni—O = 2.697 (3) Å]. The O atoms of the acetate anions form hydrogen bonds to adjacent imidazole moieties, with the free O atom forming a somewhat shorter bond [N?O = 2.679 (3) and 2.870 (4) Å]. The hydrogen bonds give rise to a two‐dimensional layer structure.     

Reaktionen von π-Organokomplexen des Nickels mit tertiären Phosphanen

Reactions of π-Organonickel Complexes with Tertiary Phosphanes In a hexane solution Ni(C₅H₅)₂ reacts with PBu₃ or Ph₂PBu forming the nickel(O) complexes Ni(PBu3)₄ or Ni(Ph₂PBu)₄ (A). Under the same conditions only one cyclopentadienyl ligand is substituted by PhPBu₂ and the nickel(I) compound (C₅H₅)Ni (PhPBu₂)₂ (B) is obtained. Products of the reactions between B and α,α′-dipyridyl, hydrogen chlorid in ether, or Ni(PhPBu₂),Cl₂ are Ni(dipy)₂, [PhPHBu₂]₂[NiCl₄], or (C₅H₅) Ni(PhPBu₂)₂Cl. By the reaction with HgCl₂ a cyclopentadienyl compound of an unknown structur is formed. The compound Ni(PhPBu₂)₄ which is analogous to A is synthesized by the reduction of bis(acety1acetonato)-nickel with Et₂AlOEt in the presence of PhPBu₂ or by the reaction of bis (cyclooctadiene-1,5)-nickel with PhPBu₂.     

Treatment activity of 0D/2D coordination complexes on gastric carcinoma by inhibiting the cancer cell viability

In the present study, via reaction of Ni(NO₃)₂·6H₂O with two flexible dicarboxylic ligands under the solvothermal reaction conditions, two new Ni(II)-containing coordination complexes with the chemical formulae of [Ni4(L1)₄(DMF)₄·2DMF]_n (1) and [Ni(L2)(DMF)]_n (2) (H2L1= 2,2'-(1,4-phenylenebis(methylene))bis(sulfanediyl)dinicotinic acid and H2L2 ?= ?2,2'-(1,2-phenylenebis(methylene))bis(sulfanediyl)dinicotinic acid) have been prepared. For the treatment of the gastric carcinoma, the Cell Counting Kit-8 kit was carried out for the detection of the gastric carcinoma cells viability after compound treatment. Additionally, the Annexin V-FITC/PI apoptosis assay was also conducted and the apoptosis levels of the gastric carcinoma cells were determined after compound exposure.     

Six new tin–sulfur containing compounds obtained under solvothermal conditions

During explorative solvothermal syntheses six new compounds containing either the [Sn₂S₆]⁴⁻ or the [SnS₄]⁴⁻ anion were obtained and structurally characterized: [Ni(1,2-dach)₃]₂Sn₂S₆·4H₂O (1) (1,2-dach = trans-1,2-diaminocyclohexane), o-{[Ni(tepa)]₂Sn₂S₆} (2) (tepa = tetraethylenepentamine), [Ni(peha)]₂Sn₂S₆·H₂O (3) (peha = pentaethylenehexamine), [Ni(aepa)]₂Sn₂S₆ (4) (aepa = N-2-aminoethyl-1,3-propandiamine), [Co(dien)]₂Sn₂S₆ (5) (dien = diethylenetriamine), and {[Mn(trien)]₂SnS₄} (trien = triethylenetetramine). In all compounds in-situ formed transition metal amine complexes act as charge compensating ligands or are bound to the thiostannate anions. Compound 2 is an orthorhombic polymorph of a recently published monoclinic compound. In compound 6 the very rare [Mn₂N₈S₂] bi-octahedron is observed as main structural motif. This compound contains a one-dimensional chain which was also observed in a pseudo-polymorphic compound. The structures of all compounds are characterized by an extended hydrogen bonding network between S atoms of the anions and the H atoms of the amine ligands and/or water molecules.     

Redox non-innocence of thioether crowns: spectroelectrochemistry and electronic structure of formal nickel(III) complexes of aza-thioether macrocycles

The Ni^II complexes [Ni([9]aneNS₂‐CH₃)₂]²⁺ ([9]aneNS₂‐CH₃=N‐methyl‐1‐aza‐4,7‐dithiacyclononane), [Ni(bis[9]aneNS₂‐C₂H₄)]²⁺ (bis[9]aneNS₂‐C₂H₄=1,2‐bis‐(1‐aza‐4,7‐dithiacyclononylethane) and [Ni([9]aneS₃)₂]²⁺ ([9]aneS₃=1,4,7‐trithiacyclononane) have been prepared and can be electrochemically and chemically oxidized to give the formal Ni^III products, which have been characterized by X‐ray crystallography, UV/Vis and multi‐frequency EPR spectroscopy. The single‐crystal X‐ray structure of [Ni^III([9]aneNS₂‐CH₃)₂](ClO₄)₆?(H₅O₂)₃ reveals an octahedral co‐ordination at the Ni centre, while the crystal structure of [Ni^III(bis[9]aneNS₂‐C₂H₄)](ClO₄)₆?(H₃O)₃? 3H₂O exhibits a more distorted co‐ordination. In the homoleptic analogue, [Ni^III([9]aneS₃)₂](ClO₄)₃, structurally characterized at 30 K, the Ni? S distances [2.249(6), 2.251(5) and 2.437(2) Å] are consistent with a Jahn–Teller distorted octahedral stereochemistry. [Ni([9]aneNS₂‐CH₃)₂](PF₆)₂ shows a one‐electron oxidation process in MeCN (0.2 M NBu₄PF₆, 293 K) at E_1/2=+1.10 V versus Fc⁺/Fc assigned to a formal Ni^III/Ni^II couple. [Ni(bis[9]aneNS₂‐C₂H₄)](PF₆)₂ exhibits a one‐electron oxidation process at E_1/2=+0.98 V and a reduction process at E_1/2=?1.25 V assigned to Ni^II/Ni^III and Ni^II/Ni^I couples, respectively. The multi‐frequency X‐, L‐, S‐, K‐band EPR spectra of the 3+ cations and their 86.2 % ⁶¹Ni‐enriched analogues were simulated. Treatment of the spin Hamiltonian parameters by perturbation theory reveals that the SOMO has 50.6 %, 42.8 % and 37.2 % Ni character in [Ni([9]aneNS₂‐CH₃)₂]³⁺, [Ni(bis[9]aneNS₂‐C₂H₄)]³⁺ and [Ni([9]aneS₃)₂]³⁺, respectively, consistent with DFT calculations, and reflecting delocalisation of charge onto the S‐thioether centres. EPR spectra for [⁶¹Ni([9]aneS₃)₂]³⁺ are consistent with a dynamic Jahn–Teller distortion in this compound.     

Synthesis,structure and thermal decomposition of [Ni(NH<Subscript>3</Subscript>)<Subscript>6</Subscript>][VO(O<Subscript>2</Subscript>)<Subscript>2</Subscript>(NH<Subscript>3</Subscript>)]<Subscript>2</Subscript>

The compound [Ni(NH₃)₆][VO(O₂)₂(NH₃)]₂ was prepared and characterized by elemental analysis and vibrational spectra. The single crystal X-ray study revealed that the structure consists of [Ni(NH₃)₆]²⁺ and [VO(O₂)₂(NH₃)]⁻ ions. As a result of weak interionic interactions V′···O_p (O_p-peroxo oxygen), ([VO(O₂)₂(NH₃)]⁻)₂ dimers are formed in the solid-state. The thermal decomposition of [Ni(NH₃)₆][VO(O₂)₂(NH₃)]₂ is a multi-step process with overlapped individual steps; no defined intermediates were obtained. The final solid products of thermal decomposition up to 600°C were Ni₂V₂O₇ and V₂O₅.     

Bis(di‐2‐pyridylamine‐κ2N2,N2′)(nitrato‐κ2O,O′)nickel(II) nitrate

<!?tpct=26.8pt>In the ionic title compound, [Ni(NO₃)(C₁₀H₉N₃)₂]NO₃, the central Ni^II atom exhibits cis‐NiN₄O₂ octahedral coordination with three chelating ligands, viz. one nitrate anion and two di‐2‐pyridylamine (dpya) molecules. A second nitrate group acts as a counter‐ion. The complex cations and the nitrate anions are also linked by N—H...O hydrogen bonds. The compound was prepared in two different reproducible ways: direct synthesis from Ni(NO₃)₂ and dpya yielded systematically twinned crystals (the twinning law is discussed), while single crystals were obtained unexpectedly from the Ni(NO₃)₂/dpya/maleic acid/NaOH system.     

Pentafluorothiophenolate derivatives of cobalt(II) and nickel(II). The molecular structure of [Ni(SC6F5)2Ph2PCH2CH2PPh2]

Summary The tetrahedral compounds [Co(SC₆F₅)₂L] (L=Ph₂P(CH₂) _n PPh₂,n=1, 2 and 3) and the squareplanar compound [Ni(SC₆F₅)₂(PhPCH₂CH₂PPh₂)] have been obtained by mathematical reactions of [MX₂L] (M=Co or Ni, X=Cl or Br) and Pb(SC₆F₅)₂. The reaction of pentacoordinate [CoCl(Ph₂PCH₂CH₂PPh₂)₂]⁺ and the lead salt yields [CoCl₂L] and [Co(SC₆F₅)₂L]. Magnetic moments, u.v. data (both in solution and solid state) and the crystal and molecular structure of the nickel compound are reported.     

Preparation and crystal structure of [μ-Ni(C5H5)P(C6H5)3] [μ-C5H5] [ZnC5H5]2, a nickel-bridged cyclopentadienylzinc dimer

[μ-Ni(C₅H₅)P(C₆H₅)₃] [μ-C₅H₅]₂ [ZnC₅H₅]₂ has been obtained from the reaction of Cp₂Zn with Ni(COD)₂ in the presence of Ph₃P and its structure determined by X-ray crystallography. It consists of two cyclopentadienylzinc moieties bridged by the Ni atom of a CpNiPPh₃ group and by a Cp group. A possible mechanism for the formation of the compound is discussed.     

Characterization and Molecular Structure of Bis(Isopropyl Xanthate) Bis(1,10-Phenanthroline) Nickel(II): [Ni(phen)2(CH3)2CHOCSS](CH3)2CHOCSS

The crystal and molecular structure of the title compound, [Ni(phen)₂(CH₃)₂CHOCSS](CH₃)₂CHOCSS has been determined by X-ray diffraction. The brown crystal is triclinic of space group Pi, with parameters a = 11.790(2), b = 12.410(3), c = 12.680(3) Å, α = 92.49(3), β = 96.54(3), γ = 117.43(3)° and Z = 2. The compound contains a six-coordinate cation and an isopropyl xanthate anion (CH₃)₂CHOCSS^?, the central Ni atom is chelated by four nitrogen atoms of two phenanthroline ligands and two sulfur atoms of an isopropyl xanthate ligand. The TG data indicate that it decomposed completely at 734°C.     

Low-dimensional compounds containing bioactive ligands. I: Crystal structure,spectroscopic, and thermal properties of the first row transition metal coordination compounds with clioquinol

Abstract  

Coordination compounds of first row transition metals from Mn to Zn with clioquinol (5-chloro-7-iodo-8-hydroxyquinoline, CQ) were prepared and characterized by infrared spectroscopy and thermal analysis. The composition of these compounds determined by elemental analysis is [M(CQ)₂(H₂O)₂] for Mn and Zn, [M(CQ)₂] for Fe, Co, Ni, and Cu, and NH₂(CH₃)₂[Ni(CQ)₃]·DMF·H₂O (DMF = N,N-dimethylformamide). X-ray structure analysis revealed that the [Ni(CQ)₂] complex is a molecular coordination compound with Ni(II) square-planarly coordinated by nitrogen and oxygen atoms of two trans-arranged bidentate molecules of clioquinol. On the other hand, NH₂(CH₃)₂[Ni(CQ)₃]·DMF·H₂O is an ionic compound containing three clioquinol molecules coordinated to the central atom in a deformed octahedral geometry thus forming a complex anion. Its negative charge is balanced by the dimethylammonium cation and the structure also contains solvated water and DMF molecules. Long-range interactions and hydrogen bonds in these two complexes were also investigated.     

Über die Kristallstrukturen der Cyanokomplexe [Co(NH3)6][Fe(CN)6], [Co(NH3)6]2[Ni(CN)4]3 · 2 H2O und [Cu(en)2][Ni(CN)4]

On the Crystal Structures of the Cyano Complexes [Co(NH₃)₆][Fe(CN)₆], [Co(NH₃)₆]₂[Ni(CN)₄]₃ · 2 H₂O, and [Cu(en)₂][Ni(CN)₄] Of the three title compounds X‐ray structure determinations were performed with single crystals. [Co(NH₃)₆][Fe(CN)₆] (a = 1098.6(6), c = 1084.6(6) pm, R3, Z = 3) crystallizes with the CsCl‐like [Co(NH₃)₆][Co(CN)₆] type structure. [Co(NH₃)₆]₂[Ni(CN)₄]₃ · 2 H₂O (a = 805.7(5), b = 855.7(5), c = 1205.3(7) pm, α = 86.32(3), β = 100.13(3), γ = 90.54(3)°, P1, Z = 1) exhibits a related cation lattice, the one cavity of which is occupied by one anion and 2 H₂O, whereas the other contains two anions parallel to each other with distance Ni…Ni: 423,3 pm. For [Cu(en)₂][Ni(CN)₄] (a = 650.5(3), b = 729.0(3), c = 796.5(4) pm, α = 106.67(2), β = 91.46(3), γ = 106.96(2)°, P1, Z = 1) the results of a structure determination published earlier have been confirmed. The compound is weakly paramagnetic and obeys the Curie‐Weiss law in the range T < 100 K. The distances within the complex ions of the compounds investigated (Co–N: 195.7 and 196.4 pm, Ni–C: 186.4 and 186.9 pm, resp.) and their hydrogen bridge relations are discussed.     

Reactivity of [Ge9{Si(SiMe3)3}3]− Towards Transition‐Metal M2+ Cations: Coordination and Redox Chemistry

Recently the metalloid cluster compound [Ge₉Hyp₃]^? ( 1 ; Hyp=Si(SiMe₃)₃) was oxidatively coupled by an iron(II) salt to give the largest metalloid Group 14 cluster [Ge₁₈Hyp₆]. Such redox chemistry is also possible with different transition metal (TM) salts TM²⁺ (TM=Fe, Co, Ni) to give the TM⁺ complexes [Fe(dppe)₂][Ge₉Hyp₃] ( 3 ; dppe=1,2‐bis(diphenylphosphino)ethane), [Co(dppe)₂][Ge₉Hyp₃] ( 4 ), [Ni(dppe)(Ge₉Hyp₃)] ( 5 ) and [Ni(dppe)₂(Ge₉Hyp₃)]⁺ ( 6 ). Such a redox reaction does not proceed for Mn, for which a salt metathesis gives the first open shell [Hyp₃Ge₉‐M‐Ge₉Hyp₃] cluster ( 2 ; M=Mn). The bonding of the transition metal atom to 1 is also possible for Ni (e.g., compound 6 ), in which one or even two nickel atoms can bind to 1 . In contrast to this in case of the Fe and Co compounds 3 and 4 , respectively, the transition‐metal atom is not bound to the Ge₉ core of 1 . The synthesis and the experimentally determined structures of 2 – 6 are presented. Additionally the bonding within 2 – 6 is analyzed and discussed with the aid of EPR measurements and quantum chemical calculations.     

Hexakis[tris­(ethyl­ene­diamine‐κ2N,N′)nickel(II)] tricyano­cuprate(I) bis­{μ‐cyano‐bis­[tricyano­cuprate(I)]} nona­hydrate

The title compound, [Ni(C₂H₈N₂)₃]₆[Cu(CN)₃][Cu₂(CN)₇]₂·9H₂O, was formed upon dissolution of a freshly prepared precipitate of CuNi(CN)₄ in ethyl­ene­diamine (en) as a result of complex redox and complexation equilibriums in the presence of air. The compound exhibits an ionic structure and contains three crystallographically independent chiral [Ni(en)₃]²⁺ cations, planar [Cu(CN)₃]²⁻ and chiral [(NC)₃Cu–(μ‐CN)–Cu(CN)₃]⁵⁻ anions, and water mol­ecules of crystallization. All metal atoms are situated on special positions. One of the Ni atoms lies on a twofold axis, whereas all other metal atoms are located on threefold axes.     

Tetraiodide von Tris(1,2‐ethandiamin)komplexen der Metalle Zink und Nickel

The isotypic compounds tris(1,2‐ethanedi­amine‐N,N′)­zinc(II) triiodide iodide, [Zn(C₂H₈N₂)₃](I₃)I, and tris(1,2‐ethanedi­amine‐N,N′)­nickel(II) triiodide iodide, [Ni(C₂H₈N₂)₃](I₃)I, contain the octahedral [M(en)₃]²⁺ cation, with M = Zn and Ni, in both enantiomeric forms, an essentially linear triiodide anion and an iodide anion. The geometries of the complex ions are as expected, e.g.d(Ni—N) = 2.123 (5), 2.127 (6) and 2.134 (5) Å, and d(Zn—N) = 2.176 (4), 2.193 (4) and 2.210 (4) Å. The shortest contact between the triiodide and iodide ions is 3.979 (1) Å for the nickel compound and 4.013 (1) Å for the zinc compound.     

Nickel(II) di(pentyl)dithiocarbamates with P ligands

Ni(II) di(pentyl)dithiocarbamates of composition [Ni(Pe₂dtc)₂], [NiX(Pe₂dtc)(PPh₃)] (X = Cl, Br, I, NCS), [Ni(NCS)(Pe₂dtc)(PBut₃)], [Ni(Pe₂dtc)(PPh₃)₂]ClO₄ and [Ni(Pe₂dtc)(PPh₃)₂]PF₆ (Pe₂dtc = di(pentyl)dithio-carbamate, PPh₃ = triphenylphosphine, PBut₃ = tributylphosphine) have been synthesized. The complexes have been characterized by the usual methods. X-ray structure analyses confirmed the nature of [NiI(Pe₂dtc)(PPh₃)] and [Ni(Pe₂dtc)(PPh₃)₂]ClO₄ complexes.     

CONTROL OF THE COORDINATION MODE OF NO2 − BY THE NATURE OF THE AMINE LIGAND. CRYSTAL STRUCTURE OF THE NEUTRAL ZIGZAG POLYMERIC COMPOUND [mer-Ni(N-(2-Aminoethyl)-1,3-Propanediamine)-(NO2)2] (I)

Abstract

A polymeric zigzag complex, [mer-Ni(N-(2-aminoethyl)-l,3-propanediamine)(NO₂)₂] (I), containing a bridging u-nitro(N,0), was obtained and its crystal structure was determined. Magnetic studies show the compound is antiferromagnetic. These results contrast to those for [Ni(3,3′-diamino-N-methyldipropylamine)(NO₂)₂] (II), which is a monomer.     

一个新颖镍配位阳离子修饰的还原型钼磷酸盐：Ni[Mo6O12(OH)3(PO4)(HPO4)3]2][Ni(H2O)2][Ni(H2O)(bipy)2]4·5H2O

水热合成并通过红外、热重、单晶X-射线衍射表征了一个新颖镍配位阳离子修饰的还原型钼磷酸盐,Ni[Mo₆O₁₂(OH)₃(PO₄)(HPO₄)₃]₂][Ni(H₂O)₂][Ni(H₂O)(bipy)₂]₄·5H₂O。单晶X-射线衍射研究表明,两个{Mo₆P₄}簇单元通过一个镍离子连接形成一个Ni[Mo₆P₄]₂二聚结构单元,其进一步和其他的镍配位阳离子连接成钼磷酸盐一维链状结构。在H₂O₂存在下的液－固体系中,使用该化合物催化氧化苯甲醛的探针反应结果表明,该化合物具有较高的催化氧化活性。