Unexpected Synthesis and Crystal Structure of Macrocyclic Nickel Complex Involving Rare S-Cl Bond

A novel complex of [NiL（OOCNH2C2H3SClO3）]·H2O was obtained unexpectedly by the reaction of [Ni（rac-L）]（ClO4）2 with l-cysteine （L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetra- azacyclotetradecane）, and characterized by EA, IR, ESI-MS and single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group P212121 with a=9.211（12）, b=14.942（19）, c=19.002（2）, Mr=563.80, V=2615.3（6）3 , Z=4, Dc=1.432 g/cm3 , F（000）=1204, μ=0.966 mm-1 , the final R=0.0565 and wR=0.1515. The central nickel（Ⅱ） ion displays a distorted six-coordinate octahedral coordination geometry by coordination with four nitrogen atoms of L, and one oxygen and one nitrogen atoms of l-cysteine. The sulfur atom of l-cysteine instead of oxygen atom links directly with the chlorine atom of perchlorate. The title complex is the first example of perchlorate salt involving the sulfur atom.

Solvothermal Synthesis,Crystal Structure and Antimicrobial Activity of a Novel Imide Nickel Complex [Ni(CH_3CONCOCH_3)_2·2(H_2O)]

A novel imide nickel complex [Ni（CH3CONCOCH3）2·2（H2O）] was synthesized by the solvothermal reaction of nickel acetate tetrahydrate and acetonitrile.What amazed us is that acetonitrile had changed into acetyl imide in enol form during the formation process of the title complex.The complex was characterized by elemental analysis,IR spectrum and X-ray single-crystal diffraction analysis.It crystallizes in the orthorhombic system,space group Pbca with a = 7.4503（7）,b = 13.1089（12）,c = 14.1303（14）,V = 1380.0（2）3,Dc = 1.420 g/cm3,Mr = 294.94,Z = 4,F（000） = 616,μ = 1.422 mm-1,the final R = 0.0487 and wR = 0.1482.The four-coordinated nickel（II） center is surrounded by 4O atoms from two imide ligands and has a distorted square planar geometry.The complex is connected to form a supramolecule with an infinite three-dimensional network through intramolecular and intermolecular hydrogen bonds.Antimicrobial activity was investigated by agar diffusion method,and the result showed that the complex was active against coli bacillus,staphylococcus aureus and bacillus subtilis.The thermal stability of the title complex was also studied by TG-DTA method.

Hydrothermal Synthesis, Crystal Structure and Surface Photo-electric Properties of a New Nickel(Ⅱ) 3-D Metalorganic Framework Constructed from the Rigid 1,4-Bis(imidazol-1-yl) benzene Ligand

A new 3-D nickel（Ⅱ） metal-organic framework（MOFs） with formula [Ni（bib）_2（SO_4）]_n（1）, where bib = 1,4-bis（imidazol-1-yl）benzene, has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and surface photovoltage spectroscopy（SPS）. Complex 1 crystallizes in monoclinic system, space group C2/c with a = 19.5988（6）, b = 9.7531（3）, c = 11.8146（4） ？, β = 96.185（3）°, V = 2245.20（12） ？~3, C_（24）H_（20）N_8NiO_4S, M_r = 575.25, D_c = 1.702 g/cm^3, Z = 4, F（000） = 1184, μ = 1.011 mm-1, the final R = 0.0293 and w R = 0.0702. X-ray diffraction analyses indicated that the center Ni^（2＋） ion is six-coordinated with an O_2N_4 donor set of two μ_2-SO_4^（2–） and four bib ligands, resulting in an ideal octahedral geometry. Topological analysis on complex 1 considers each Ni^（2＋） as a 6-connected node, while bib and sulfate ion as linkers, giving an α-Po topology with short Schl？fli symbol 412·63. In the crystal packing, the components interact with pairs of intermolecular C–H×××O hydrogen bonds. The SPS of 1 indicates that there are positive response bands in the range of 300~600 nm showing photo-electric conversion properties.

Template Syntheses and Crystal Structures of Hexaaza Macrocyclic Complexes with C-Methyl Substituents

Two new macrocyclic complexes with C-methyl substituents on the framework, namely, [CuL]（ClO4）2 （L = 5,12-dimethyl-1,8-dihydroxyethyl-1,3,6,8,10,13-hexaazacyclotetradecane） 1 and [NiL]（ClO4）2 2, have been synthesized and structurally characterized through X-ray diffraction analysis. Also, crystal structure of [CuL^1]（ClO4）2 （L^1 = 1,8-dimethyl- 1,3,6,8, [ 0,13- hexaazacyclotetradecane） 3 has been determined. Crystal data for 1： C14H32C12CuN6O10, Mr = 578.90, monoclinic, P2 1/n, α = 8.3529（11）, b = 10.8105（17）, c = 13.3709（17） ,A, β = 105.189（10）°, V= 1165.2（3） A3, Z = 2, Dc = 1.650 g/cm^3, F（000） = 602, λ（MoKct） = 0.71073 A,μ = 1.229 mm ^-1, R = 0.0474 and wR = 0.0895 for 2771 observed reflections （I 〉 2σ（Ⅰ））. Crystal data for 2： C14H32C12N6NiO10, Mr = 574.07, monoclinic, P2 1/c, a = 8.3636（12）, b = 12.997（2）, c = 10.764（2） A, β = 99.31（2）°, V = 1154.7（3） A^3, Z = 2, DC = 1.651 g/cm^3, F（000） = 600, λ（MoKa） = 0.71073 A,μ = 1. 134 mm^-1, R = 0.0380 and wR = 0.0796 for 2670 observed reflections （i 〉 2σ（Ⅰ））. Crystal data for 3： C 10H26Cl2CuN6O8, Mr = 492.81, monoclinic, P2 1/n, a = 8.4860（17）, b = 8.6320（17）, c = 12.662（3） ,A,β = 103.40（3）°, V = 902.2（3）A^3, Z = 2, Dc = 1.814 g/cm^3, F（000） = 510, λ（MoKa） = 0.71073A, μ = 1.562 mm^-1, R = 0.0505 and wR = 0.1061 for 1967 observed reflections （I〉 2σ（Ⅰ））. Complexes 1 and 2 are isostructural with the metal ions situated at the inversion center/Hydrogen bonds between O atoms of pendant and perchlorate anion give rise to a two-dimensional supramolecular layer. The Cu（Ⅱ） ions of compounds 1 and 3 adopt distorted axially-elongated octahedral coordinate geometry, and the nickel（Ⅱ） ion in complex 2 is four-coordinated with a square-planar configuration.

Syntheses and Crystal Structures of Two Novel 1-D Metal Complexes with Dicyanamide:[Zn(pheen)(dca)_2]n and [Cu(quin)_2(dca)_2]n

The two complexes [Zn(phen)(dca)2]n 1 (phen = 1,10-phenanthroline, dca = di-cyanamide) and [Cu(quin)2(dca)2]n 2 (quin = quinoline) were synthesized by self-assembly reactions of Zn(CH3COO)24H2O with Nadca and phen ligands, and CuCl22H2O with Nadca and quin ligands, respectively. Their crystal structures were determined by single-crystal X-ray diffraction analyses. Crystallographic data for complex 1: (C16H8N8Zn)n, Mr = 377.67, monoclinic, space group P21/c, a = 10.1322(5), b = 11.0218(6), c = 14.1351(6) ? β = 101.077(2), V = 1549.1(1) 3, Z = 4 , Dc = 1.619 g/cm3, (MoKα) = 1.602 mm-1, F(000) = 760, R = 0.0698 and wR = 0.1558; and for complex 2: (C22H14N8Cu)n, Mr = 453.95, orthorhombic, space group Cmc21, a = 16.679(4), b = 9.153(2), c = 12.937(3) ? V = 1975.0(7) 3, Z = 4, Dc = 1.527 g/cm3, (MoKα) = 1.134 mm-1, F(000) = 924, R = 0.0486 and wR = 0.0981. The structures of complexes 1 and 2 consist of infinite zigzag chains, and their metal atoms have slightly distorted square pyramidal coordination environments with two N atoms of phen or quin ligands and three nitrile N atoms of dca ligands. The secondary long ZnN bonds and p-p stacking interactions make the chains into a three-dimensional network in complex 1.

Synthesis and Crystal Structure of Dicyanamide (5,7,7,12,14,14-Hexamethyl-1,4,8,11-tetraazacyclo- tetradecane) Copper(II) Percholatehydrate

The copper(II) complex [Cu(teta)N(CN)2](ClO4)H2O (teta = 5,7,7,12,14,14- hexamethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized and the crystal structure was determined by single-crystal X-ray diffraction. Crystal data: C18H38ClCuN7O5, monoclinic, space group P21/n, a = 8.796(3), b = 11.885(4), c = 23.054(9) , b = 97.540(4)o, V = 2389.3(15) 3, Mr = 531.54, Z = 4, Dc = 1.478 g/cm3, F(000) = 1124, ?= 1.070 mm-1, the final R = 0.0566 and wR = 0.1162 for 4749 observed reflections (I > 2s(I)). The center copper ion is coordinated by five nitrogen atoms in a square pyramidal geometry, with four from the macrocyclic ligand teta and the other one from a nitrile nitrogen atom of dicyanamide which is coordinated to the metal atoms as uni-dentate manner via nitrile nitrogen atom.

Synthesis and Crystal Structure of Bis(dicyanamide) (5,7,7,12,14,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane) Nickel(Ⅱ)

The nickel(Ⅱ)complex [Ni(teta){N(CN)2}2] (teta = 5,7,7,12,14,14-hexamehyl-1,4, 8,11-tetraazacyclotetradecane) was synthesized and its structure has been determined by single- crystal X-ray diffraction. Crystal data: C20H36N10Ni, monoclinic, space group P21/c, a = 9.632(2), b = 11.833(2), c = 10.613(2) ? b = 93.46(3), V = 1207.4(4) ?, Mr = 475.30, Z = 2, Dc = 1.307 g/cm3, F(000) = 508, m(MoKa) = 0.831 mm-1, R = 0.0446 and wR = 0.1274 for 2423 observed reflections with I > 2s(I). The center nickel ion is coordinated by six nitrogen atoms, four from the macrocyclic ligand teta and the other two from two dicyanamides. The dicyanamide is coordinated to the metal atoms as uni-dentate manner via nitrile nitrogen atom.

Structure Studies on New Types of Macrocyclic Compounds Part V．Crystal Structure of Nickel（II） Complex of 5，12－Diphenyl－7，14－dimethyl－1，4，8，11－tetraazacyclotetradecane－N＇，N－diacetic Acid

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Synthesis and Crystal Structure of a New Mononuclear Nickel(Ⅱ) Mixed Complex Derived from 2-Aminoethyl-bi(3-bi-aminopropyl)amine with 1,10-Phenanthroline

The mixed complex [Ni（L）（L＇）]（ClO4）2 has been synthesized using 2-aminoethyl- bi（3-bi-aminopropyl）amine with phen （1,10-phenanthroline） in the presence of Ni（Ⅱ） ion, and its structure was determined by X-ray diffraction. The crystal crystallizes in monoclinic, space group P21/c with a = 13.713（2）, b = 13.1466（19）, c = 14.780（2） A°, β= 97.620（3）°, V = 2640.9（7） A °^3, F（000） = 1272, Z = 4, Dc = 1.540 g/cm^3, R = 0.0536 and wR = 0.1207. The Ni^2＋ ion is sixcoordinated to furnish a distorted octahedral geometry.

Molecular and Supramolecular Structures of a Nickel(Ⅱ) Complex with a Macrocyclic Ligand

The crystal structure of the title complex, [NiL], has been determined by using X-ray analysis (H2L = 2,3-dioxo-5,6:13,14-dibenzo-7,12-bis(methoxycarbonyl)-1,4,8,11-tetraazacyclotetra- deca-7,11-diene). Crystal data: C22H18N4O6Ni, Mr = 493.11, triclinic, space group P, a = 9.128(6), b = 9.941(7), c = 12.396(8) ? a = 107.11(1), b = 106.14(1), g = 97.69(1), V = 1003.9(11) 3, Z = 2, Dc = 1.631 g/cm3, m(MoKa) = 1.018 mm-1, F(000) = 508, R = 0.0584 and wR = 0.0981 for 1724 observed reflections with I > 2s(I). The Ni(II) atom is coordinated by four nitrogen donors of the macrocyclic ligand with a slightly distorted square-planar geometry. In the crystal, the CH…O hydrogen bonds link the complex molecules to form infinite 1D chains which are further linked by p…p stacking interactions to form chain-pairs.

Synthesis, Crystal Structure and Antimicrobial Activity of a Novel Ni(II) Complex

A new nickel（Ⅱ） complex, C34H38N8NiO4, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group P21/c with a = 11.715（5）, b = 12.328（5）, c =11.113（5）A, β= 92.589（5）°, Z = 2, Dc = 1.411 g/cm^3,μ = 0.658 mml, the final R = 0.0427 and wR = 0.1099 for 2229 observed reflections with I 〉 2σ（I）. The complex is a centrosymmetric plane in which nickel（Ⅱ） is coordinated in a regular octahedron to the ligand phenytoin through the nitrogen atoms of ethylenediamine, imine and amine. The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method, and found to be active against the four test bacterial organisms. Preliminary screening for antimicrobial activities showed that the title complex is quite active against standard strains of Salmonella species, Staphylococcus aureus, Bacillus pumilus and Eschierichia coli.

Synthesis and Crystal Structure of Bis[O,O'-bis(4-tert-butylphenyl)dithiophosphate]nickel(Ⅱ)

A new O,O＇-bis（4-tert-butylphenyl）dithiophosphate complex Ni[SSP（OC6H4But- p）2]2 （1） was synthesized and characterized by elemental analysis, IR, 1H NMR, thermogravimetric analysis （TGA） and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 12.8440（3）, b = 6.18686（12）, c=26.3018（5） , β=92.6135（18）°, V = 2087.87（7） 3, Z = 2, Dc = 1.345 g/cm3, μ = 0.780 mm-1, the final R = 0.0316 and wR = 0.0748 （Ⅰ 〉2σ（Ⅰ））. A total of 4269 unique reflections were collected, of which 3621 with Ⅰ 〉 2σ（Ⅰ） were observed. The NiII atom lies on an inversion center and is chelated by two （p-ButC6H4O）2PSS-ligands in a [NiS4] square-planar geometry with Ni-S bonds of 2.2408（5） and 2.2444（5） , respectively. A stepwise 1D chain structure is constructed via intermolecular S…S and C-H…S interactions. According to our knowledge this is the first case that intermolecular S…S interaction is observed in mononuclear transition metal complex of O,O＇-dialkyldithiophosphates.

Synthesis and Crystal Structure of a Novel Two-dimensional Supramolecular Complex Ni(C_6H_7N)_2(SCN)_2(H_2O)_2

A novel nickel（Ⅱ） complex Ni（C6H7N）2（SCN）2（H2O）2 （C14H18N4NiO2S2, Mr= 397.15） has been synthesized and structurally characterized by X-ray analysis. The crystal is of monoclinic, space group P21/c with a = 9.212（2）, b = 13.132（3）, c = 7.8794（19） A°, β = 99.142（3）°, Z = 2, V = 41.1（4） A°^3 Dc= 1.402 g/m^3, μ（MoKα） = 1.264 mm^-1, F（000） = 412, R1 = 0.0303 and wR2= 0.0794 for 1387 observed reflections （I 〉 2σ（I））. The title complex shows a 2-D network structure extended by twelve-membered Ni2O2H2S2C2N2 ring and ten-membered NiO2H3S2CN ring.

Synthesis and Crystal Structure of a Novel Three-dimensional Complex Ni(Iz)_2(Bdc)(H_2O)_2 (Iz = Imidazole,Bdc = 1,4-Benzenedicarboxylate)

A novel nickel（Ⅱ） complex Ni（Iz）2（Bdc）（H2O）2 （Iz = imidazole, Bdc = 1,4-benzenedicarboxylate） has been synthesized and structurally characterized by X-ray analysis. The crystal is of monoclinic, space group P2 1/n with a = 5.5079（5）, b = 15.0973, c = 9.9825（9） A, β = 90.2380（10）°, C14H16N4NiO6, Mr = 395.02, Z = 2, V = 830.08（13） A^3 Dc = 1.580 g/cm^3, μ（MoKa） = 1.208 mm^-1, F（000） = 408, R = 0.0234 and wR = 0.0603 for 1379 observed reflections （I 〉 2σ（I））. In the title complex, adjacent nickel（Ⅱ） ions are bridged through the oxygen atoms of carboxylic groups in syn-anti conformation, yielding an infinite one-dimensional chain. These chains are linked to each other to form a 3-D network structure by three kinds of hydrogen-bonding interactions.

Synthesis and Crystal Structure of [Cu_3(dmpzm)_4(μ-1,3-dca)_2(dca)_4]·2H_2O (dmpzm=1,1'-Methylenebis-(3,5-dimethyl-1H-pyrazole),dca=dicyanamide)

The title compound, [Cu3（dmpzm）4（μ-1,3-dca）2（dca）4]·2H2O （dmpzm = 1,1＇-methylenebis（3,5-dimethyl-lH-pyrazole）, dca = dicyanamide） 1·2H2O, was synthesized via the reaction of CuCl2·2H2O with dmpzm and Na（dca）, and characterized by elemental analysis and IR spectra. 1·2H2O crystallizes in the monoclinic system, space group C2/m with a = 13.578（3）, b = 16.769（3）, c = 14.769（3） A, β = 104.10（3）° V = 3261.4（11） A^3, Z = 2, Dc = 1.466 g/cm^3, T = 153（2） K, C56H68N34O2Cu3, Mr = 1440.09, F（000） = 1490,μ（MoKa） = 1.040 mm^-1, S = 1.150, R = 0.0553 and wR = 0.1123 for 2744 observed reflections with I 〉 2σ（I）. The central copper atom is chelated by two dmpzm ligands and coordinated by two bridging dca anions, forming a slightly distorted octahedral geometry. The two external copper atoms adopt a square-pyramidal coordination geometry, coordinated by one chelating dmpzm ligand and one bridging and two terminal dca anions. Two intermolecular hydrogen bonding interactions result in the formation of a 2D （4,4） hydrogen-bonded network.

Syntheses and Crystal Structures of Two Nickel(Ⅱ) Complexes [Ni(dmpzm)_2(L)]Cl·nH_2O (L=HCO_2,OAc;n=2,3;dmpzm=1,1'-Methylenebis(3,5-dimethyl-1H-pyrazole))

Reactions of NiCl2-6H2O with dmpzm and formic or acetic acid at PH = 7 produced the two title compounds, [Ni（dmpzm）2（HCO2）]Cl·2H2O 1 and [Ni（dmpzm）2（OAc）]C2·H2O 2 （dmpzm = 1,1 ＇-methylenebis（3,5-dimethyl-lH-pyrazole））. 1 and 2 were characterized by elemental analysis, IR spectra, and thermogravimetric analysis. 1 crystallizes in the orthorhombic system, space group Pcca with a = 18.700（2）, b = 8.6843（9）, c = 18.098（2）A, V= 2939.1（5）A^3, Z = 4, Dc = 1.319 g/cm^3, T = 193 K, C23H37CINsNiO4, Mr = 583.75, F（000） = 1232, p（MoKa） = 0.792 cm^-1, S = 1.079, R = 0.0772 and wR = 0.1958 for 2265 observed reflections with I〉 2σ（I）. 2 crystallizes in the orthorhombic system, space group Pcca with a = 17.011（3）, b = 18.630（4）, c = 19.300（4）A, V = 6117（2）A^3, Z = 8, Dc = 1.337 g/cm^3, T= 193（2） K, C24H41C1N8NiO5, Mr = 615.79, F（000） = 2608, μ（MoKa） = 0.768 cm^-1, S = 1.059, R = 0.0518 and wR = 0.1109 for 5124 observed reflections with I 〉 2σ（I）. The Ni atoms in 1 or 2 are chelated by two dmpzm ligands and one formate or acetate anion, forming slightly distorted octahedral geometries. In the crystals of 1 or 2, intermolecular hydrogen bonding interactions result in the formation of 2D hydrogen-bonded frameworks.

Synthesis and Crystal Structure of a Complex Bimetallic Salt [Ni(trans_[14]diene)] [Ni (mnt)_2]

The title compound has been synthesized by the reaction of [Ni(trans[14]diene)]I2 with Na[Ni(mnt)2] in water and THF, where [trans[14]diene]= 5, 7,7, 12, 14, 14-hexamethyl-1, 4, 8, 11-tetraazacyclotetradeca-4, 11-diene and mnt2- = cis-1, 2-dicyano-1,2-ethylenedithiolato. Its crystal structure has been determined by X-raycrystallography analysis with 4827 independent reflections (Fo>4σ(F0). The bimetallic complex salt [Ni (trans [14] diene )] [Ni (mnt )2] (C24 H32N8Ni2S4, Mr = 678. 24 )crystallizes in the triclinic system with space group P1, a = 9. 2911 (9), b= 11. 7075(12), c=15. 799(2) A, α=68. 384(7), β=79. 324(7), γ=67. 581(6)°, V=1474. 9(3) A3, Dc=1. 527 Mg/m3, Z=2, λ=0. 71073 A, μ=1. 589mm-1, F(000) =704,R=0. 0367. The structure consists of slightly distorted Square planar units [Ni(trans[14]diene)]2+ and [Ni(mnt)2]2-.

Syntheses and Crystal Structures of Lanthanide Complexes of New 15-Membered Macrocyclic Ligands with Three Pendant Acetato Groups

Two new 15-membered functionalized macrocycles, dioxo^polyazacycloalkanes with three pendant acetato groups, have been synthesized by the condensation reaction of DTPA dianhydride (DTPA=diethylenetriaminepentaacetic acid) with 1,2-diaminopropane, (15-DTPA-1,2-pn), or 1,2-diaminocyclohexane, (15-DTPA-1,2-cy). Their lanthanide complexes [Ln(15-DTPA-1,2-pn)(H 2O)] 2 [Ln=Eu (1), Gd (2)] and [Ln(15-DTPA-1,2-cy)(H 2O)] 2 [Ln=Eu (3), Gd (4)] were also prepared. Single crystal X-ray diffraction analyses of complexes 2 and 4 show that they have dimeric structures in solid state; each metal ion is nine-coordinated in a distorted tricapped-trigonal prism. In complex 4, the coexistence of two diastereoisomeric molecules in the crystal lattice was observed.

Synthesis,Crystal Structure and Fluorescence Property of a New Trinuclear Nickel(Ⅱ) Complex Bridged by 2,6-Pyridine Dicarboxylic Acid

A new trinuclear nickel complex,[Ni3（pdc）3（2,2＇-bipy）3（H2O）2]·2H2O（H2pdc = pyridine 2,6-dicarboxylic acid,2,2＇-bipy = 2,2＇-bipyridine） has been hydrothermally synthesized and characterized by IR,elemental analysis and X-ray diffraction methods.Crystal data for this complex：monoclinic,space group P21/n,a = 21.206（4）,b = 10.002（2）,c = 28.066（6）,β = 108.18（3）°,C51H41N9Ni3O16,Mr = 1212.06,V = 5.656（2） nm3,Dc = 1.423 g·cm-3,μ（MoKα） = 1.062 mm-1,Z = 4,F（000） = 2488,GOOF = 1.034,the final R = 0.0543 and wR = 0.1237 for 6149 observed reflections with Ⅰ 〉 2σ（Ⅰ）.In the complex,three nickel（Ⅱ） ions are bridged by the pyridine 2,6-dicarboxylic acid groups,and all nickel（Ⅱ） ions are seven-coordinated by nitrogen atoms of 2,2＇-bipyridine and pyridine 2,6-dicarboxylic acid and oxygen atoms from pyridine 2,6-dicarboxylic and water to adopt a severely distorted pentagonal bipyramidal geometry.The emission and excitation peaks of the complex in ethanol solutions are located at 336 and 316 nm,respectively.