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1.
建方方  赵朴素  肖海连  张书圣 《中国化学》2002,20(10):1134-1137
IntroductionImidazolehasattractedconsiderableinterestasalig andinmanybiologicalsystemsinwhichitprovidesapo tentialbindingsiteformetalions .1Imidazoleitselfisanunidentateligandandformscomplexeswithmetalionsthroughitstertiarynitrogenatom .Somecomplexesofi…  相似文献   

2.
Microwave‐assisted synthesis has been used to obtain the family of dodecanuclear NiII complexes [Ni12(NO3)(MeO)12(MeC6H4CO2)9(MeOH)10(H2O)2][ClO4]2 ( 1 ), [Ni12(NO3)(MeO)12(BrC6H4CO2)9(MeOH)10(H2O)2][ClO4]2 ( 2 ), [Ni12(CO3)(MeO)12(MeC6H4CO2)9(MeOH)10(H2O)2]2[SO4] ( 3 ) and [Ni12(NO3)(MeO)12(MeC6H4CO2)9(MeOH)8(H2O)7][NO3]2 ( 4 ). They contain three {Ni4O4} cubane units which template around a central μ6 anion, either NO3? or CO32?. Their magnetic properties have been studied by superconducting quantum interference device (SQUID) magnetometry and high‐field EPR measurements. The nanostructuration of the Ni12 species on mica surfaces is studied by AFM and grazing‐incidence X‐ray diffraction, which reveal the formation of polycrystalline thin layers.  相似文献   

3.
Three crystal structures of Ni compounds containing bis(pyridine-2-carbaldehyde thiosemicarbazone) ligand (HL), namely (pyridine-2-carbaldehyde thiosemicarbazonato)(pyridine-2-carbaldeyde thiosemicarbazone) nickel(II) nitrate hydrate [Ni(HL)L][NO3]·(H2O) (1), bis(pyridine-2-carbaldehyde thiosemicarbazone) nickel(II) dinitrate [Ni(HL)2][NO3]2·(2a), and bis(pyridine-2-carbaldehyde thiosemicarbazone) nickel(II) dinitrate dihydrate [Ni(HL)2][NO3]2·2(H2O) (2b) are determined by X ray diffraction methods. Comparative structural studies are carried out.  相似文献   

4.
Four macrocyclic Schiff-base cobalt complexes, [CoL1][NO3]2 · 3H2O, [CoL2][NO3]2 · 4H2O, [CoL3][NO3]2 · 4H2O and [CoL4][NO3]2 · 2H2O, were synthesized by reaction of salicylaldehyde derivatives with 1,4-bis(3-aminopropoxy)butane or (±)-trans-1,2-diaminocyclohexane and Co(NO3)2 · 6H2O by template effect in methanol. The metals to ligand ratio of the complexes were found to be 1:1. The Co(II) complexes are proposed to be tetrahedral geometry. The macrocyclic Co(II) complexes are 1:2 electrolytes as shown by their molar conductivities (ΛM) in DMF (dimethyl formamide) at 10?3 M. The structure of Co(II) complexes is proposed from elemental analysis, Ft-IR, UV–visible spectra, magnetic susceptibility, molar conductivity measurements and mass spectra. Electrochemical and thin-layer spectroelectrochemical studies of the complexes were comparatively studied in the same experimental conditions. The electrochemical results revealed that all complexes displayed irreversible one reduction processes and their cathodic peak potential values (E pc) were observed in around of ?1.14 to 0.95 V. It was also seen that [CoL1][NO3]2 · 3H2O and [CoL2][NO3]2 · 4H2O exhibited one cathodic wave without corresponding anodic wave but, [CoL3][NO3]2 · 4H2O and [CoL4][NO3]2 · 2H2O showed one cathodic wave with corresponding anodic wave, probably due to the presence of different ligand nature even if the complexes have the same N2O2 donor set. In view of spectroelectrochemical studies [CoL3][NO3]2 · 4H2O showed distinctive spectral changes in which the intensity of the band (λ = at 316 nm, assigned to n → π* transitions) decreased and a new broad band in a low intensity about 391 nm appeared as a result of the reduction process based on the cobalt center in the complex.  相似文献   

5.
Polyoxometallates are capable of including transition metals in their crystal structures as either discrete cations or heteroatoms. The title compound crystallizes with triclinic symmetry and consists of a centrosymmetric [V10O28]6? anion, a trimeric {[Na(H2O)3][Ni(H2O)6][Na(H2O)3]}4+ cation, an [Ni(H2O)6]2+ cation and four water molecules of crystallization. The compound possesses two Ni atoms (each on independent inversion centres), one as a discrete cation and one in a disodium–nickel trimeric cation involved in the one‐dimensional polycation–polyanion hybrid polymer. The polymers are bound together via hydrogen bonds to the water mol­ecules and the nickel(II) hexahydrate cation. Several structures of decavanadate compounds having transition metal atoms, monovalent cations and [V10O28]6? anions in the ratio 2:2:1 have been reported previously. However, the present compound differs from these in its arrangement of monovalent cations and transition metal atoms.  相似文献   

6.
The title complexes, hexaaquacobalt(II) bis(μ‐pyridine‐2,6‐dicarboxylato)bis[(pyridine‐2,6‐dicarboxylato)bismuthate(III)] dihydrate, [Co(H2O)6][Bi2(C7H4NO4)4]·2H2O, (I), and hexaaquanickel(II) bis(μ‐pyridine‐2,6‐dicarboxylato)bis[(pyridine‐2,6‐dicarboxylato)bismuthate(III)] dihydrate, [Ni(H2O)6][Bi2(C7H4NO4)4]·2H2O, (II), are isomorphous and crystallize in the triclinic space group P. The transition metal ions are located on the inversion centre and adopt slightly distorted MO6 (M = Co or Ni) octahedral geometries. Two [Bi(pydc)2] units (pydc is pyridine‐2,6‐dicarboxylate) are linked via bridging carboxylate groups into centrosymmetric [Bi2(pydc)4]2− dianions. The crystal packing reveals that the [M(H2O)6]2+ cations, [Bi2(pydc)4]2− anions and solvent water molecules form multiple hydrogen bonds to generate a supramolecular three‐dimensional network. The formation of secondary Bi...O bonds between adjacent [Bi2(pydc)4]2− dimers provides an additional supramolecular synthon that directs and facilitates the crystal packing of both (I) and (II).  相似文献   

7.
The Chloride Nitrate PrCl2(NO3) · 5 H2O with Cationic and Anionic Complexes according to [PrCl2(H2O)6][PrCl2(NO3)2(H2O)4] Green single crystals of PrCl2(NO3) · 5 H2O have been obtained from an aqueous solution of PrCl3 and Pr(NO3)3. The crystal structure [monoclinic, P2/c, Z = 4, a = 1228.8(3), b = 648.4(1), c = 1266.0(4) pm, β = 91.91(3)°] contains cationic and anionic Pr3+ complexes according to [PrCl2(H2O)6][PrCl2(NO3)2(H2O)4]. Both nitrate groups of the anionic complex act as bidentate chelating ligands. Hydrogen bonds are observed with water molecules as donors and chlorine as well as oxygen atoms as acceptors.  相似文献   

8.
A method for the preparation of new solvated clusters of the composition [M6Br12(H2O)6][HgBr2X2] · 12H2O (M?Nb, Ta; X?Cl, Br, I) is given. The cubic crystals of [Nb6Br12(H2O)6][HgBr4] · 12H2O 1 and [Ta6Br12(H2O)6][HgBr4] · 12H2O 2 were characterized by the X-ray structure analysis: 1 : cubic, space group Fd3 m, a = 21.0072(6) Å, Z = 8, R = 0.051 (Rw = 0.066); 2 : cubic, space group Fd3 m, a = 20.9698(1) Å, Z = 8, R = 0.038 (Rw = 0.050). 1 and 2 contain octahedral cluster cation [M6Br12(H2O)6]2+ and tetrahedrally arranged [HgBr4]2? anion. The M? M bond distances are 2.949(1) Å for 1 and 2.9000(8) Å for 2 . The Hg? Br bond distances in [HgBr4]2? anion are 2.614(2) Å in 1 and 2.622(2) Å in 2 . The crystal packing patterns of the isostructural clusters 1 and 2 involve the three-dimensional hydrogen bond network; the crystalline water molecules act as donors of hydrogen to the bromine atoms of the cluster and [HgBr4]2? units, whereas the coordinated water molecules form hydrogen bonds to the crystalline water molecules. [Nb6Br12(H2O)6][HgBr4] · 12H2O is diamagnetic and semiconducting with the activation energy, Ea = 0.20 eV.  相似文献   

9.
Acrylamide complexes of metal nitrates: [M(O‐OC(NH2)CHCH2)n(H2O)m][NO3]2 (M = Co( 1 ), Ni( 2 ) (n = 6 and m = 0) and Zn( 3 ) (n = 4 and m = 2)) have been determined by using single crystal X‐ray diffraction analysis. All complexes crystallize in the triclinic space group . The structures of 1 and 2 represent octahedral species [M(AAm)6]2+ (AAm = O‐OC(NH2)CHCH2 and M = Co or Ni) and uncoordinated nitrate ions. The structure of 3 involves the octahedral cation [Zn(AAm)4(H2O)2]2+ in which the Zn2+ environment includes oxygen atoms of four acrylamide and two water molecules that are stabilized using ionic nitrate ions. The observations of the solid‐state IR spectroscopic vibrational frequencies of these acrylamide complexes are in agreement with the crystal structures.  相似文献   

10.
Organically templated metal sulfates are relatively new. Six amine‐templated transition‐metal sulfates with different types of chain structures, including a novel iron sulfate with a chain structure corresponding to one half of the kagome structure, were synthesized by hydro/solvothermal methods. Amongst the one‐dimensional metal sulfates, [C10N2H10][Zn(SO4)Cl2] ( 1 ) is the simplest, being formed by corner‐linked ZnO2Cl2 and SO4 tetrahedra. [C6N2H18][Mn(SO4)2(H2O)2] ( 2 ) and [C2N2H10][Ni(SO4)2(H2O)2] ( 3 ) have ladder structures comprising four‐membered rings formed by SO4 tetrahedra and metal–oxygen octahedra, just as in the mineral kröhnkite. [C4N2H12][VIII(OH)(SO4)2]?H2O ( 4 ) and [C4N2H12][VF3(SO4)] ( 5 ) exhibit chain topologies of the minerals tancoite and butlerite, respectively. The structure of [C4N2H12][H3O][FeIIIFeII F6(SO4)] ( 6 ) is noteworthy in that it corresponds to half of the hexagonal kagome structure. It exhibits ferrimagnetic properties at low temperatures and the absence of frustration, unlike the mixed‐valent iron sulfate with the full kagome structure.  相似文献   

11.
Hexaaquaaluminum methanesulfonate crystals, [Al(H2O)6][CH3SO3]3 were synthesized by a hydrothermal reaction of Al(OH)3 with methanesulfonic acid. Single-crystal diffraction determination revealed that Al3+ was coordinated by six water molecules in octahedral geometry, while the CH3SO3 anion connected with Al3+ through coordinated water molecules by hydrogen bonds. The six-coordinate environment of Al was also determined by 27Al MAS NMR measurement. Thermogravimetric analysis and Fourier transform infrared spectroscopy showed that the decomposition intermediate at 265–365 °C was Al2(μ-OH)(CH3SO3)5 and the final product was amorphous Al2O3 residue with about 0.8 wt% SO3 at 520–800 °C. A pure phase of [Al(H2O)6][CH3SO3]3 was confirmed by powder X-ray diffraction analysis. Esterification of n-butyric acid with n-butanol and ketalization of cyclohexanone with glycol catalyzed by [Al(H2O)6][CH3SO3]3 and Al2(μ-OH)(CH3SO3)5, respectively, proceeded in 100% yield by continuously removing the produced water. In the case of tetrahydropyranylation of n-butanol at room temperature in dichloromethane, the catalytic activity of [Al(H2O)6][CH3SO3]3 was much lower than that of Al2(μ-OH)(CH3SO3)5. Furthermore, both [Al(H2O)6][CH3SO3]3 precursor and Al2(μ-OH)(CH3SO3)5 catalysts could be recycled.  相似文献   

12.

The compound, [Ni(phen)3]NO3 · C2H5OP(O)O · 3H2O, was obtained by the reaction of Ni(NO3)2, C2H5OP(OH)2 and 1,10-phenanthroline in 95% EtOH solution, and was characterized using IR and UV spectra and magnetic susceptibility measurements over the temperature range 75-300 K. The red crystal is triclinic of space group P&1macr;, with lattice parameters a = 12.462(3), b = 13.416(3), c = 13.422(3) Å, f = 75.88(3), g = 64.75(3), n = 65.87(3)°, and Z = 2. The coordinated cation contains a six-coordinate nickel atom chelated by three phenanthroline ligands, resulting in a distorted octahedral arrangement with the six Ni-N distances ranging from 2.086(2) to 2.113(3) Å. In addition to the nickel coordination complex, there are two anions, NO3 and C2H5OP(O)O-, and three water molecules which complete the crystal structure. In the solid state, the title compound forms a three dimensional network structure through hydrogen bonds. The intermolecular hydrogen bonds connect the [Ni(phen)3]2+, NO3, C2H5OP(O)O- and H2O molecules.  相似文献   

13.
Three hexakis(imidazole)metallo complexes of Co, Cd and Ni were synthesized and spectroscopically characterized. The crystal and molecular structures have been determined by X-ray crystallography analysis. The metal ions have an octahedral geometry with the MN6 chromophore. The electrochemical experimental results indicate that both [Co(Im)6]C12·2HCl·2H2O (1) and [Ni(Im)6]C12·4H2O (3) [Im=imidazole] could interact with DNA mainly by intercalation.  相似文献   

14.
Water-soluble daidzein derivatives, [Ni(H2O)6](C16H11O4SO3)2⋅10H2O and [Zn(H2O)6] (C16H11O4SO3)2⋅10H2O (C16H11O4SO3, 7-methoxy-4′-hydroxylisoflavone-3′-sulfonate) were synthesized and their crystal structures were determined by X-ray diffraction analysis. The crystals of them all belong to triclinic crystal system, space group P . The results show that the two derivatives consist of metal cation [Ni(H2O)6]2+ and [Zn(H2O)6]2+, anion C16H11O4SO3 and H2O. Ni2+ and Zn2+ are the centers of the two compounds, respectively. A hydrophilic region is built by a variety of hydrogen bonds among [Ni(H2O)6]2+ or [Zn(H2O)6]2+, C16H11O4SO3 and the lattice water molecules. Aromatic π–π stacking interactions assemble the isoflavone skeletons into a column and the columns form a hydrophobic region of daidzein derivatives. The sulfo-groups bridge the hydrophilic and hydrophobic region as well as the inorganic and organic components.  相似文献   

15.
The crystal structures of two square tetracyanocomplexes were determined. [Ni(dien)2][Ni(CN)4]·2H2O (NDNCH) and [Ni‐(dien)2][Pd(CN)4] (NDPC) (dien = diethylene triamine) exhibit ionic structures consisting of mer‐[Ni(dien)2]2+ cations and [Ni(CN)4]2‐ or [Pd(CN)4]2‐ anions, respectively. Moreover, the structure of NDNCH is completed by two water molecules of crystallisation. In both compounds hydrogen bonds contribute to the stabilisation of the structure. NDNCH dehydrates on air quickly yielding anhydrous [Ni(dien)2][Ni(CN)4] (NDNC). Its thermal decomposition proceeds in a complicated process followed by aerial oxidation of metallic nickel to NiO.  相似文献   

16.
Na5[CuO2][CO3], Na5[CuO2][SO3], Na5[CuO2][S], and Na5[CuO2][SO4] were obtained as single crystals and powders from reactions of Na2O, Cu2O, and Na2X with X = CO32—, SO32—, S2—, and SO42—, respectively. A redox reaction between CdO and Co metal occurs in the presence of Na2O and Na2X, yielding Na5[CoO2][X] with X = CO32— and S2—. From a mixture of Na2SO4, CdO and Na2O in Ni‐containers we observed the formation of Na5[NiO2][S] single crystals. Single crystals of Na25[CuO2]5[SO4]4[S] can be grown by annealing Na5[CuO2][SO3] at 600 °C, leading to the decomposition of SO32—, yielding SO42— and S2— at 550 °C. The structures have been determined from single crystal data and powder data. All structures contain the isolated complex [MO2]3— in a dumb‐bell like arrangement. The main feature of these compounds is that the anions SO42—, SO32—, CO32— and S2— are not connected to the transition metal. The formation of Na5[CuO2][X] (X = S2—, SO42—, SO32—, CO32—) has been studied by thermal analysis and in situ X‐ray diffraction techniques. Infrared spectra confirm the presence of SO42—, SO32—, and CO32—, respectively, in the structures.  相似文献   

17.
利用水热法合成了两种过渡金属配合物为模板剂的含水硼酸盐晶体Co(en)3[B4O5(OH)4]Cl·3H2O(1) 和 [Ni(en)3][B5O6(OH)4]2·2H2O (2),并通过元素分析、X射线单晶衍射、红外光谱及热重分析对其进行了表征。化合物1晶体结构的主要特点是在所有组成Co(en)33+, [B4O5(OH)4]2–, Cl– 和 H2O之间通过O–H…O、O–H…Cl、N–H…Cl和N–H…O四种氢键连接形成网状超分子结构。化合物2晶体结构的特点是[B5O6(OH)4]–阴离子通过O–H…O氢键连接形成沿a方向有较大通道的三维超分子骨架,模板剂[Ni(en)3]2+阳离子和结晶水分子填充在通道中。  相似文献   

18.

Reaction of a freshly prepared Ni(OH)2?2 x (CO3) x ·yH2O with maleic acid in H2O at room temperature afforded [Ni(H2O)6][Ni(H2O)2(C4H2O4)]·4H2O, which consists of [Ni(H2O)6]2+ cations, [Ni(H2O)2(C4H2O4)]2? anions and lattice H2O molecules. Ni atoms in cations are octahedrally coordinated and Ni atoms in anions are each octahedrally coordinated by bidentate chelating maleato ligands and two water molecules at trans positions. Cations and anions are interlinked by hydrogen bonds to form 1D chains, which are hexagonally arranged and connected by the lattice water molecules. When heated in a flowing argon stream, the compound decomposes, with complete dehydration being followed by dissociation of nickel maleate into NiO and maleic anhydride.  相似文献   

19.
The ability of heterometallic Ge(IV) and Sn(IV) complexes [Co(H2O)6][Ge(HCitr)2] (I), [Co(H2O)6] [Sn(HCitr)2] (II), [Ni(H2O)6][Ge(HCitr)2] (III), [Ni(H2O)6][Sn(HCitr)2] (IV), [Mg(H2O)6][Ge(HCitr)2] (V), and [Mg(H2O)6][Sn(HCitr)2] (VI) (H4Citr is citric acid) to activate polycondensation of maleic and phthalic anhydrides with ethylene glycol was studied. Copolymerization of modified poly(glycol maleate phthalate) with triethylene glycol dimethacrylate was performed, and the copolymer characteristics were determined.  相似文献   

20.
Piperanol thiosemicarbazone (HL) has been interacted with Ag+, Co(II), Ni(II) or Cu(II) binary to produce [Ag(HL)]EtOH · NO3, [Ag2(L)(H2O)2]NO3, [Co(L)3], [Cu(L)(H2O)3(OAc)]H2O or [Ni(L)2] and template with Ag+ to form [Cu2Ag2(L)2(OH)2(H2O)4]NO3 and [NiAg(L)2(H2O)2]NO3. The prepared complexes are characterized by microanalysis, thermal, magnetic and spectral (IR, 1H NMR, ESR and electronic) studies. Ag+ plays an important role in the complex formation. The variation in coordination may be due to the presence of two different metal ions and the preparation conditions. The outside nitrate is investigated by IR spectra. The outer sphere solvents are detected by IR and thermal analysis. Ni(II) complexes are found diamagnetic having a square-planar geometry. Cu(II) is reduced by the ligand to Cu(I). The cobalt complex is found diamagnetic confirming an air oxidation of Co(II) to Co(III) having a low spin octahedral geometry. The ligand and its metal complexes are found reducing agents which decolorized KMnO4 solution in 2N H2SO4. CoNS and NiNS are the residual parts in the thermal decomposition of [Co(L)3] and [Ni(L)2].  相似文献   

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