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1.
The crystal structure of the complexes [Co(DH)2(Tu)2]2[BeF4]·C2H5OH (I) and [Co(DfH)2(Tu)2][BF4] 0.5H2 (II) (where DH? is the dimethylglyoxime monoanion, DfH? is the α-benzyldioxime monoanion, and Tu is thiourea) has been determined by X-ray diffraction analysis. The coordination polyhedron of the Co3+ atom is an N4S2 octahedron formed by four nitrogen atoms of the dioxime molecule and two sulfur atoms of the fragments of thiourea (Tu); the latter have parallel and perpendicular orientations relative to the dioxime residue. The deviation of the cobalt atom from the four-angle plane (formed by the nitrogen atoms of the dimethylglyoxime residues) does not exceed 0.019 Å. The Co-N and Co-S distances vary from 1.877(3) Å to 1.901(3) Å and from 2.280(1) Å to 2.307(1) Å, respectively. The statistically disordered cations [BeF4]2? and [BF4]? play an important role in crystal formation — they form a complex system of hydrogen bonds.  相似文献   

2.
The new Co(III) dioximates [Co(DH2)(D)(Thio)2]2[TiF6] ·2DMF (I), [Co(NioxH)2(Thio)2]2[TiF6] · 2.25H2O (II), and [Co(DpgH)2(Thio)2]2[TiF6] · 4DMF · 1.5H2O (III) have been synthesized and studied (DH2 and D are, respectively, the dimethylglyoxime molecule and doubly charged anion; NioxH and DpgH are singly charged anions of 1,2-cyclohexanedione dioxime and diphenylglyoxime, respectively; Thio is thiourea; DMF is dimethylformamide). The composition and structure of the complexes have been studies by IR, UV, and NMR spectroscopy. The crystal structures have been determined by X-ray crystallography. The hydrogen bonds in the structures are formed by fluorine atoms of the [TiF6]2? anion with Co(III) complex cations and solvent molecules of crystallization. The amino groups of coordinated thiourea molecules are also involved in the hydrogen bond system, which is responsible for their different arrangement with respect to the equatorial planes of the Co(III) complex cations.  相似文献   

3.
Novel macrocyclic anion receptors based on the principle of anion-π interactions were reported. By means of both post-macrocyclization modification protocol and the stepwise fragment coupling approach, functionalized oxacalix[2]arene[2]triazines bearing two other electron-deficient (hetero)aromatic rings on the lower rim were efficiently synthesized. The resulting oxacalix[2]arene[2]triazine macrocyclesadopt 1,3-alternate conformation, yielding therefore an expanded electron-deficient cavity or space consisting of two triazine rings and two appending aromatic rings. Spectroscopic titration study showed the selective interaction of the pentafluorophenyl-substituted oxacalix[2]arene[2]triazine with azide and fluoride in solution with the binding constants (K(1:1)) ranging from 1.33 × 10(3) to 3.52 × 10(3) M(-1).  相似文献   

4.
5.
A new halophosphate crystal Sr3P3O10Cl was grown in molten chloride flux media. It crystallizes in the centrosymmetric orthorhombic space group Pnma (No. 62) with a = 10.617(2) Å, b = 10.736(2) Å, and c = 8.7354(17) Å. In the structure, the basic building unit is the [P3O10]5− anion, which is consist of three PO4 tetrahedra by sharing the corner oxygen atoms. The two Sr atoms and the Cl atom are linked to construct an infinite [Sr3Cl]5+ chain. The [P3O10]5− anions are interconnected with the [Sr3Cl]5+ chains to form a three-dimensional frameworks. Additionally, the first-principle calculation was employed to obtain the band structures and densities of states.  相似文献   

6.
Two new decavanadate metal compounds, [Co(pyim)3]2[V10O28]·7H2O (1) and [Ni(pyim)3]2[H2V10O28]·4H2O (2) (pyim?=?2-(2-pyridyl)-imidazole), have been synthesized under hydrothermal conditions and characterized by elemental analysis, single-crystal X-ray diffraction analysis, infrared spectra, powder X-ray diffraction analysis, and thermogravimetric analysis. Crystallographic analysis reveals that 1 is constructed from [V10O28]6?, metal cation [Co(pyim)3]3+, and water. [V10O28]6? clusters are connected by waters through O–H?O hydrogen bonds to form a sheet structure which is further connected by N–H?O hydrogen bonds to form a 3-D supermolecular framework. In 2, although [Ni(pyim)3]2+ is similar to [Co(pyim)3]3+ in 1, the M?O cluster anion is protonated [H2V10O28]4?.  相似文献   

7.
The [NpO2(DPPMO2)2Cl][NpO2Cl4] complex (where DPPMO2 = bis(diphenylphosphino)methanedioxide) contains the linear neptunyl group, {NpO2}2+, with two bidentate P=O donor ligands. Coordinating anion Cl? fills the fifth equatorial coordination site yielding a complex of general formula [NpO2(DPPMO2)2X]2[Y] (1) (where X = Cl? and Y = [NpO2Cl4]2?. Reaction between our newly prepared neptunium starting material [NpO2Cl2(thf)]n and phosphinimine ligand produced crystals of [Ph3PNH2]2[NpO2Cl4] (2). Compounds 1 and 2 have been structurally characterised.  相似文献   

8.
Two couples of new compounds templated by the polyanion [SiW12O40]4?,[Hbix][CuI(bix)]3[SiW12O40]·4H2O (1) and [CuII(H2O)(Hbix)2(bix)]2[CuII(H2O)2(Hbix)2(bix)][SiW12O40]3·4H2O (2) (bix = 1,4-Bis(imidazol-1-ylmethyl)benzene), [CuI(bbi)]4[SiW12O40]·2H2O (3) and [CuII(bbi2)]2[SiW12O40] (4) (bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) were hydrothermally synthesized, and characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses and single X-ray diffraction. Compounds 1 and 2 were synthesized from the same reactants but exhibited distinct structures which could be ascribed to the different ratios of the reactant bix to CuII. In compound 1, the higher ratio of bix results in the transformation of the CuII to CuI, the [SiW12O40]4? templates direct the CuI–bix coordination polymers to form a 3D supramolecular framework with grid-like channels along two directions. The [SiW12O40]4? templates in compound 2 locate in the voids of the 3D supramolecular network constructed by CuII–bix coordination polymers, which exhibits the interdigitation fashion in both the formation of the 2D layer and the 3D framework. Compounds 3 and 4 were synthesized similar to 1 and 2, except for the change of bix to bbi. In compound 3, the CuI–bbi polymers form a supramolecular metal–organic host framework with rhombic channels in which the SiW12 templates reside. Compound 4 shows a framework with hexagonal channels constructed by CuII–bbi coordination polymers which accommodated the SiW12 templates.  相似文献   

9.
The reaction of pentaphenylantimony with mercury iodide affords the ionic complex [Ph4Sb] 2 + [Hg2I6]2?·Ph2Hg (I). The [Ph4Sb] 2 + [Hg2I6]2? (II) and [Ph4Sb] 2 + [Cd2I6]2? (III) complexes are synthesized from tetraphenylantimony iodide and mercury and cadmium iodides. The [Ph4Sb] 2 + [Hg4I10]2? complex (IV) is prepared from tetraphenylantimony 2,4-dimethylbenzenesulfonate and mercury iodide. According to the X-ray diffraction data, the Sb atom in the [Ph4Sb]+ cations of complex I has virtually ideal tetrahedral coordination (the CSbC angles are 108.09°–109.64°). In the central square fragment Hg2I2 of the [Hg2I6]2? anion, the Hg-Ibr bond lengths are 2.825 and 3.075 Å, and the terminal iodine atoms are more strongly bonded to the mercury atoms (Hg-Iterm 2.691 and 2.700 Å). The [Cd2I6]2? anion in complex III has a similar structure (the Cd-Ibridg and Cd-Iterm distances are 2.865, 2.872 and 2.723, 2.748 Å, respectively). The anions in complex IV are joined by I…Hg (3.651 Å) and I…I (4.058 Å) interactions into an infinite dimeric network.  相似文献   

10.
Barium cerate doped by trivalent rare earth metal ions is a potentially huge component of materials for electrochemical industry due to its high protonic conductivity. However, the poor chemical stability especially in the presence of CO2, SO2 or H2O, resulting in decreasing the mechanical durability of obtained materials, limits their possible applications. The new approach towards stable ceramic protonic conductors with high electrical conductivity is presented. Thermal stability of yttrium doped (10 mol%) of BaCeO3 was enhanced by forming the composite material BaCe0.9Y0.1O3–BaWO4 (10 mol% of BaWO4). The synthesis was performed by solid-state reaction method. The detailed study of thermal decomposition of starting powders mixture was performed using thermogravimetry and differential thermal analysis (TG/DTA) techniques combined with Evolved Gas Analysis (EGA—mass spectrometry). Structure, phase composition and microstructure together with thermal stability of sintered materials were determined. The exposition tests were performed to characterise the stability of composites in carbon dioxide and water vapour-rich atmospheres. The samples were exposed to atmosphere containing CO2/H2O (7 % of CO2 in air, 100 % RH) at temperature of 25 °C for 300 h. Thermal analysis supplied with mass spectrometry was applied to analyse the materials after the test. The results of this experiment showed better chemical resistance of composite material—BaCe0.9Y0.1O3 with 10 mol% of BaWO4 compared to single phase material.  相似文献   

11.
Two new borate clusters, [NH3(CH2)3NH3]2[B14O20(OH)6] (1) and [NH3(CH2)6NH3]2[B14O20(OH)6] (2), have been made under solvothermal conditions and characterized by single-crystal X-ray structural analysis. Also their IR and UV–Vis spectroscopy, thermogravimetric analysis, and elemental analysis have been investigated, respectively. Crystal data for 1: triclinic, P-1, a = 8.8049(4) Å, b = 9.1585(5) Å, c = 10.1912(5) Å, α = 74.925(4)°, β = 80.987(4)°, γ = 67.495(5)°, Z = 1. Crystal data for 2: triclinic, P-1, a = 9.2010(4) Å, b = 9.8663(4) Å, c = 11.4191(4) Å, α = 107.014(4)°, β = 92.514(3)°, γ = 107.265(4)°, Z = 1. The structures consist of isolated 8-membered boron ring made of the [B7O10(OH)3]2?cluster subunits. UV–Vis spectral investigation indicates that they are wide-band-gap semiconductors. Fluorescence spectroscopy indicates that they are potential blue light materials.  相似文献   

12.
The kinetics of the reaction between [ReN(H2O)-(CN)4]2− with different κ2 N,O-donor ligands (quin and 2,3-dipic, respectively) have been studied in the pH 4–12 range in aqueous solution. Two consecutive reaction steps with the formation of the [ReN(η1-quin)(CN)4]3− and [ReN(μ2-quin) (CN)3]2− complexes, respectively, were spectrophotometrically observed and kinetically investigated. The same reaction mechanism is proposed for these two ligands. The first fast reaction (for quin) is attributed to the aqua substitution of [ReN(H2O)(CN)4]2− with forward and reverse rate constants of 1.96(5) × 10−1 M−1 s−1 and 5.6(3) × 10−2 s−1, while a rate of 2.64(3) M−1 s−1 was observed for the reaction between the conjugate base [ReN(OH)(CN)4]3− and quin at 40.2 °C. Due to small absorbance changes, it was difficult to obtain any good quality data for the fast reactions for 2,3-dipic. The second, slower reaction is attributed to cyano substitution with rate constants (k 3 K 1) of 4.17(4) × 10−3 for quin and 4.68(7) × 10−3 M−1 s−1 for 2,3-dipic, at 80.02 °C, respectively. The acid dissociation constant for the aqua complex was spectrophotometrically determined as 11.58(3) and 11.54(2) and kinetically as 11.51(8) and 11.41(1), at 80.4 °C, respectively. Negative values of −83.5(2) and −144.1(2) J K−1 mol−1 as well as the of 71.4(3) and 47.3(3) kJ mol−1, for the slow quin and 2,3-dipic reactions, respectively, point to an ordered transition state where bond formation is responsible for the major driving force of the reaction. The and for the fast forward reaction of quin is indicative of expected associative activation in the transition state. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

13.
Summary 4-Chloro-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazole (3) was prepared by chlorination of2 which could also be converted directly to 2-methylpyrimidino[4,5:4,5]-thiazolo[3,2-a]benzimidazol-4-thiol (4). Nucleophilic substitution of3 with alcohols, phenols, primary amines, secondary amines, sodium azide, and mercaptoacetic acid gave the corresponding derivatives. The thiol derivative4 was reacted with alkyl/aralkyl halides, phenacyl bromide derivatives, bromoacetone, chloroanilides, bromomalonic ester, and ethyl bromoacetate to afford compounds of potential pharmacological interest.
Synthese und Reaktionen neuer 4-Chlor-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazole
Zusammenfassung 4-Chlor-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazol (3) wurde durch Chlorierung von2, welches auch direkt zu 2-Methylpyrimidino[4,5:5,4]thiazolo[3,2-a]-benzimidazol-4-thiol (4) umgesetzt werden kann, hergestellt. Nucleophile Substitution von3 mit Alkoholen, Phenolen, primären Aminen, sekundären Aminen, Natriumazid und Mercaptoessigsäure ergab die entsprechenden Derivate. Das Thiolderivat4 wurde mit Alkyl/Alkarylhalogeniden, Phenacylbromidderivaten, Bromaceton, Chloraniliden, Brommalonsäureester und Bromessigsäureethylester zu potentiell pharmakologisch interessanten Verbindungen umgesetzt.
  相似文献   

14.
Dendrimer5arethree-dimensional,highorderedoligomericandPOlymericcomPOundS,whicharemo1ecular-1evelcontrolofsize,shapes,surfacechentistry,toPOlogyandflexibility.'.'Calixarenesarecyclicoligomers,whichhavebeenextensive1ystudiedinordertoobtalnnewhostsbyappropriatefiJnctionalizationoftheparentmolecule.3,#Besides,calixarenesareattractivecandidatesfOrpolponctionalcoresindendriticmolecules,esPeciallybytheconvergentgroWthaPProach.'ltisinterestingthatthemoleculeofcombinationofcalixarenewithdendritic…  相似文献   

15.
The heteroleptic dmit complex [Et4N]2[Ni2(C2S4)(C3S5)2] has been prepared by the reaction of NiCl2.H2O with Na2dmit, NaSC2H4OH in the MeOH solution. The compound has been characterized by X-ray diffraction study, IR and UV-Vis spectroscopy. Crystallographic data : space group: P21/n, a=11.843(2), b=11.079(1), c = 15.404(1)(), β=110.33(1)°, V = 1895.1()3, Z=2, Dc=1.62 g/cm3, μ=17.6 cm-1, F(000)=956, R=0.052, Rw=0.061. In the structure of the title complex, the tto (tto=tetrathioxalato) ligand in bridging form is chelated to two nickel atoms and dmit (dmit=1,3-dithiole-2-thione-4,5-dithiolate) ligands coordinated to nickel atoms.  相似文献   

16.
The NMR method has been employed for investigation of the fibrillar lithium trimolybdate. The results indicate that the ratio of the number of OH groups to that of water molecules in the coordination sphere of the central molybdenum atom is dependent on the temperature.  相似文献   

17.
18.
The formation of binary complex salts containing gold(III) in the cation and palladium(II) in the anion in the systems [(Bipy)AuCl2]+-[PdCl4]2? occurs by transfer of the N,N-electron-donating chelating ligand bipyridine and the chloride ligands between the gold-containing cation and the palladium-containing anion. The resulting neutral salt [(Bipy)PdCl2] crystallizes together with the anion [AuCl4]? from acetonitrile-water (1 : 1-1 : 2, v/v) to give the complex salt (NH 4 + )0.20[(Bipy)AuCl 2 + ]1.04[(Bipy)PdCl2]0.96[AuCl 4 ? ]0.76PdCl 4 2? ]0.24 with a total Au : Pd ratio of 3 : 2. The ammonium cation is formed from acetonitrile upon its hydrolysis most likely catalyzed by Pd complexes. Quantum-chemical calculations were performed to study the transfer of the chelating ligand theoretically.  相似文献   

19.
p-Perfluoroalkylealix[4]arenes were prepared readily from the reaction of calix-[4]arene with perfluoroalkyl iodides in the presence of sodium dithionite or sodium hydroxy-methanesulfinate under mild conditions,These fluorine-containing calixarenes showed bettersolubilities in common organic solvents as compared to their nonperfluoroalkylation analogand formed inclusion complexes with many neutral molecules as well as fluorocarbons.  相似文献   

20.
The reaction of thiamine chloride hydrochloride with a solution of palladium chloride in hydrochloric acid gave a protonated thiamine salt [HTA]2[PdCl4]Cl2 · 2H2O (I) (TA is 4-methyl-3-[(2??-methyl-4??-amino-3??,4??-dihydropyrimidinyl-5??)methyl]-5-(2-hydroxyethyl)thiazolium cation, C12H16N3O2S). The crystal structure of I was determined by X-ray diffraction. The crystals are triclinic: a = 11.459(8) ?, b = 12.239(8) ?, c = 6.910(1) ?, ?? = 103.24(3)°, ?? = 76.95(3)°, ?? = 106.04(3)°, Z = 2, space group P $\bar 1$ . The structural units of I are doubly charged [HTA]2+ cations, [PdCl4]2? and Cl? anions, and crystallization water molecules combined by hydrogen bonds and electrostatic interactions. The planar thiazolium and pyrimidine rings are in the F conformation, ??t = 1.0°, ??p = ?86.6°, and the dihedral angle between the planes is 85.5°. The torsion angles of the hydroxyethyl group are as follows: C(9)C(10)C(11)O(1), 175.6°; S(1)C(9)C(10)C(11), 33.2°; it is involved in the hydrogen bond with the free Cl? anion. The sulfur atom forms a short (3.052 ?) intermolecular S-Cl contact with the chlorine atom of the [PdCl4]2? anion, which forms supramolecular chains.  相似文献   

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