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1.
The reaction of Nb2O5 and Ta2O5 with an aqueous solution of hydrofluoric acid, HF in the presence of biphenyl-20-crown-6 (BP20C6, L1) or [1.5]dibenzo-18-crown-6 ([1.5]DB18C6, L2) results in the complexes [L1·(H3O)][NbF6] (1), [L1 (H3O)][TaF6] (2), [2L2·(H7O3)][NbF6] (3) and [2L2·(H7O3)][TaF6] (4). Complexes 1–4 were identified by the elemental and X-ray structural analysis and IR spectroscopy. Complexes 1 and 2 are isostructural, with the H3O+ oxonium ion embedded in one crown molecule via OH···O hydrogen bonds. Complexes 3 and 4 represent the supramolecular isomers distinctive by the crown conformations and crystal packing, with the (H7O3)+ cation enclosed in the cage of two crown molecules. Being poor H-bond acceptors, NbF6 and TaF6 anions do not compete with the crown oxygen atoms for the oxonium hydrogen atoms, but are involved in the numerous C–H···F short contacts responsible for the extended supramolecular architectures in all cases. A change of crown ethers’ conformation in complexes 1–4 and a correlation between the degree of proton hydration and an accessibility of the crown ether oxygen atoms is observed. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   

2.
The structures of two salts of flunarizine, namely 1‐bis[(4‐fluorophenyl)methyl]‐4‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazine, C26H26F2N2, are reported. In flunarizinium nicotinate {systematic name: 4‐bis[(4‐fluorophenyl)methyl]‐1‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazin‐1‐ium pyridine‐3‐carboxylate}, C26H27F2N2+·C6H4NO2, (I), the two ionic components are linked by a short charge‐assisted N—H...O hydrogen bond. The ion pairs are linked into a three‐dimensional framework structure by three independent C—H...O hydrogen bonds, augmented by C—H...π(arene) hydrogen bonds and an aromatic π–π stacking interaction. In flunarizinediium bis(4‐toluenesulfonate) dihydrate {systematic name: 1‐[bis(4‐fluorophenyl)methyl]‐4‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazine‐1,4‐diium bis(4‐methylbenzenesulfonate) dihydrate}, C26H28F2N22+·2C7H7O3S·2H2O, (II), one of the anions is disordered over two sites with occupancies of 0.832 (6) and 0.168 (6). The five independent components are linked into ribbons by two independent N—H...O hydrogen bonds and four independent O—H...O hydrogen bonds, and these ribbons are linked to form a three‐dimensional framework by two independent C—H...O hydrogen bonds, but C—H...π(arene) hydrogen bonds and aromatic π–π stacking interactions are absent from the structure of (II). Comparisons are made with some related structures.  相似文献   

3.
Characterization of Distortional Isomers of the Anions Pentacyano-oxo-molybdate(IV) and of Tetracyano-aqua-oxo-molybdate(IV) in the Solid State. Crystal Structures of [(C6H5)4P]3[MoO(CN)5] · 7 H2O (green), [(C6H5)4As]2[MoO(OH2)(CN)4] · 4 H2O (blue), and [(C6H5)4P]2[MoO(OH2) (CN)4] · 4 H2O (green) Preparation of a series of salts containing the new pentacyano-oxo-molybdate(IV) anion is described: Cs2H[MoO(CN)5] (blue), [(CH3)4N]2H[MoO(CN)5] · 2 H2O (blue) and [Cr(en)3] [MoO(CN)5] · 4 H2O (green). The green [(C6H5)4P]3[MoO(CN)5] · 7 H2O crystallizes triclinic in the space group P1 . The molybdenum(IV) center is in an pseudo-octahedral environment of a terminal oxo-group (d(Mo?O); 1.705(4) Å), a CN? group in the trans-position (d(Mo? C): 2.373(6) Å), and four equatorial CN? groups (averaged d(Mo? C): 2.178 (Å). The blue and green salts exhibit v(Mo?O) stretching frequencies at 948 cm?1 and 920 cm?1, respectively. Blue and green salts containing the [MoO(OH2)(CN)4]2? anion and [(C6H5)4P]+ or [(C6H5)4As]+ cations have been prepared and characterized by single crystal crystallography. [(C6H5)4P]2[MoO(OH2)(CN)4] · 4 H2O (green) and [(C6H5)4As]2[MoO(OH2)(CN)4] · 4 H2O (blue) crystallize monoclinic in the space group C—P21/n. They are considered to be distortional isomers of the complex anion: the green species has a Mo?O bond distance of 1.72(2) Å whereas for the blue species d(Mo?O) = 1.60(2) Å is found; the corresponding v(Mo?O) frequencies are at 920 cm?1 and 980 cm?1.  相似文献   

4.
The reaction of MCl4(thf)2 (M = Zr, Hf) with 1,4-dilitiobutane in diethyl ether at –25 °C or at 0 °C with a molar ratio of 1 : 3 yields the homoleptic “ate” complexes [(thf)4Li] [{(thf)Li}M(C4H8)3] 1 - Zr (M = Zr) and 1 - Hf (M = Hf). The crystalline compounds form ion lattices with solvent-separated [(thf)4Li]+ cations and [{(thf)Li}M(C4H8)3] anions. The NMR spectra at –20 °C show magnetic equivalence of the M–CH2 and of the β-CH2 groups of the butane-1,4-diide ligands on the NMR time scale. Analogous reactions of MCl4(thf)2 with 1,4-dilithiobutane with a molar ratio of 1 : 2 proceed unclear. However, single crystals of [Li(thf)4] [HfCl5(thf)] ( 2 ) can be isolated with the hafnium atom in a distorted octahedral coordination sphere of five chloro and one thf ligand. NMR spectra allow to elucidate the time-dependent degradation of 1-Hf and 1-Zr in THF and toluene at 25 °C via THF cleavage. Addition of tmeda to a solution of 1-Zr allows the isolation of intermediately formed [{(tmeda)Li}2Zr(nBu)2(C4H8)2] ( 3 ).  相似文献   

5.
The compounds M(CO)5 · THF (M = Cr, Mo, W) react with sodium mercaptide, NaSR (R = C6F5, C6H5, C2H5), to give the mercapto-pentacarbonylmetallate anions [M(CO)5 · · SR]?. The preparation of some pentafluorophenylthio complexes, e. g. [(C6H5)3P]2MSC6F5(M = Cu, Ag, Au), [(C6H5)3P]2Hg(SC6F5)2, is reported.  相似文献   

6.
Novel mononuclear oxovanadium(IV) and manganese(III) complexes [VO(L1)2·H2O] (1); [VO(L2)2·H2O] (2); [VO(L3)2·H2O] (3); [Mn(L1)2]ClO4·H2O (4); [Mn(L2)2] ClO4·H2O (5); [Mn(L3)2]ClO4·H2O (6) were prepared by condensation of 1 mol of VOSO4·5H2O or Mn(OAc)3· 2H2O with 2 mol of ligand HL1, HL2 or HL3 (where HL1 = 4-[(2-hydroxy-ethylamino)-methylene]-5-methyl-2- phenyl-2,4-dihydro-pyrazol-3-one; HL2=4-[(2-hydroxy-ethylamino)-methylene]-5-methyl-2-p-tolyl-2,4-dihydro-pyrazol-3-one; HL3=4-{4-[(2-hydroxy-ethyl-amino)-methyl]-3-methyl-5-oxo-4,5-dihydropyrazol-1-yl} benzene sulfonic acid). The resulting complexes were characterized by elemental analyses, molar conductance, magnetic and decomposition temperature measurements, electron spin resonance, FAB mass, IR and electronic spectral studies. From TGA, DTA and DSC, the thermal behaviour and degradation kinetic were studied. Electronic spectra and magnetic susceptibility measurements indicate distorted octahedral stereochemistry of oxovanadium(IV) complexes and regular octahedral stereochemistry of manganese(III) complexes. Hamiltonian and bonding parameters found from ESR spectra indicate the metal ligand bonding is partial covalent. The X-ray single crystal determination of one of the representative ligand was carried out which suggests existence of amine-one tautomeric form in the solid state. The 1H-NMR spectra support the existence of imine-ol form in solution state. The LC-MS studies sustain the1H-NMR result. The electronic structure of the same representative ligand was optimized using 6-311G basis set at HF level ab initio studies to predict the coordinating atoms of the ligand.  相似文献   

7.
Phase formation in the ZrO(NO3)2-NaF(HF)-H3PO4-H2O system was studied at 20°C and 2.0–14.5 wt % ZrO2 in the initial solution along sections with molar ratios PO 4 3? /Zr = 0.5 and 1.5 and also in the presence of hydrogen fluoride at Na/Zr = 1 and PO 4 3? /Zr = 0.5, 1.0, and 1.5. Crystalline zirconium hydrophosphate Zr(HPO4)2 · H2O, fluorozirconates Na5Zr2F13 and Na7Zr6F31 · 12H2O, fluorophosphatozirconates NaH2Zr3F3(PO4)4 · 3H2O and NaZr2F6(PO4) · 4H2O, and amorphous NaZrO0.5F(PO4) · 4H2O (provisional composition) were separated at room temperature. NaH2Zr3F3(PO4)4 · 3H2O and NaZr2F6(PO4) · 4H2O were prepared for the first time and were studied by crystal-optical, elemental, and thermal analyses, X-ray powder diffraction, IR spectroscopy, scanning electron microscopy (SEM), and X-ray microanalysis. Na7Hf6F31 · 12H2O was found to exist in a mixture with the hydrophosphate.  相似文献   

8.
Naphthaldimines containing N2O2 donor centers react with platinum(II) and (IV) chlorides to give two types of complexes depending on the valence of the platinum ion. For [Pt(II)], the ligand is neutral, [(H2L1)PtCl2]·3H2O (1) and [(H2L3)2Pt2Cl4]·5H2O (3), or monobasic [(HL2)2Pt2Cl2]·2H2O (2) and [(HL4)2Pt]·2H2O (4). These complexes are all diamagnetic having square-planar geometry. For [Pt(IV)], the ligand is dibasic, [(L1)Pt2Cl4(OH)2]·2H2O (5), [(L2)Pt3Cl10]·3H2O (6), [(L3)Pt2Cl4(OH)2]·C2H5OH (7) and [(L4)Pt2Cl6]·H2O (8). The Pt(IV) complexes are diamagnetic and exhibit octahedral configuration around the platinum ion. The complexes were characterized by elemental analysis, UV-Vis and IR spectra, electrical conductivity and thermal analyses (DTA and TGA). The molar conductances in DMF solutions indicate that the complexes are non-ionic. The complexes were tested for their catalytic activities towards cathodic reduction of oxygen.  相似文献   

9.
In the title compound, [(CH3)2(C7H7)NH][(C6F5)3B(OH)] or C9H14N+·C18HBF15O?, the distorted tetrahedral borate anions are strongly hydrogen bonded to the substituted ammonium cations. The N?O separation in the N—H?O hydrogen bond is 2.728 (3) Å.  相似文献   

10.
Four salts, namely, 2,4,6-triaminopyrimidinium 6-chloronicotinate dihydrate, C4H8N5+·C6H3ClNO2·2H2O, (I), 2,4,6-triaminopyrimidinediium pyridine-2,6-dicarboxylate dihydrate, C4H9N52+·C7H3NO42−·2H2O, (II), 2,4,6-triaminopyrimidinediium sulfate monohydrate, C4H9N52+·SO42−·H2O, (III), and 2,4,6-triaminopyrimidinium 3,5-dinitrobenzoate dihydrate, C4H8N5+·C7H3N2O6·2H2O, (IV), were synthesized and characterized by X-ray diffraction techniques. Proton transfer from the corresponding acid to the pyrimidine base has occurred in all four crystal structures. Of the four salts, two [(I) and (IV)] exist as monoprotonated bases and two [(II) and (III)] exist as diprotonated bases. In all four crystal structures, the acid interacts with the pyrimidine base through N—H…O hydrogen bonds, generating an R22(8) ring motif. The sulfate group mimics the role of the carboxylate anions. The water molecules present in compounds (I)–(IV) form water-mediated large ring motifs. The formation of water-mediated interactions in these crystal structures can be used as a model in the study of the hydration of nucleobases. Water molecules play an important role in building supramolecular structures. In addition to these strong hydrogen-bonding interactions, some of the crystal structures are further enriched by aromatic π–π stacking interactions [(I) and (II)].  相似文献   

11.
Reaction of (TBBP)AlMe ? THF with [Cp*2Zr(Me)OH] gave [(TBBP)Al(THF)?O?Zr(Me)Cp*2] (TBBP=3,3’,5,5’‐tetra‐tBu‐2,2'‐biphenolato). Reaction of [DIPPnacnacAl(Me)?O?Zr(Me)Cp2] with [PhMe2NH]+[B(C6F5)4]? gave a cationic Al/Zr complex that could be structurally characterized as its THF adduct [(DIPPnacnac)Al(Me)?O?Zr(THF)Cp2]+[B(C6F5)4]? (DIPPnacnac=HC[(Me)C=N(2,6‐iPr2?C6H3)]2). The first complex polymerizes ethene in the presence of an alkylaluminum scavenger but in the absence of methylalumoxane (MAO). The adduct cation is inactive under these conditions. Theoretical calculations show very high energy barriers (ΔG=40–47 kcal mol?1) for ethene insertion with a bridged AlOZr catalyst. This is due to an unfavorable six‐membered‐ring transition state, in which the methyl group bridges the metal and ethene with an obtuse metal‐Me‐C angle that prevents synchronized bond‐breaking and making. A more‐likely pathway is dissociation of the Al‐O‐Zr complex into an aluminate and the active polymerization catalyst [Cp*2ZrMe]+.  相似文献   

12.
New mixed complex compound bis(dibenzo-18-crown-6)(tetrachlorocuprato(II)-Cl, Cl′, Cl″, Cl?) dipotassium diaqua(dibenzo-18-crown-6)potassium dichlorocuprate(I)dibenzo-18-crown-6 [(CuCl4)[K(Db18C6)]2]·[K(Db18C6)(H2O)2]+·[CuCl2]?·Db18C6 was prepared and its structure was studied by the X-ray structural analysis. The structure was found to be disordered. The asymmetric part of its unit cell contains 1/4 of each of its four components. For a given [CuCl4]2? anion its Cu2+ cation is disordered over two equally probable positions and its independent Cl atom is disordered over three positions differing by occupancy. In this structure two [K(Db18C6)]+ fragment of the complex molecule and the complex cation [K(Db18C6)(H2O)2]+ are of guest-host type with K+ cation as the guest. In this structure the statistically disordered alternating cations and Db18C6 molecules form infinite chains. The statistically disordered [CuCl2]? anions also form infinite chains.  相似文献   

13.
Adducts of cucurbit[6]uril with Ca2+ and trinuclear cluster chloroaquacomplexes (H9O4)2(H7O3)2[(Ca(H2O)5)2(C36H36N24O12)]Cl8·0.67H2O (1) and [(Ca(H2O)5)2(C36H36N24O12)]× [Mo3O2S2Cl6(H2O)3]2·13H2O (2) are obtained and structurally characterized. The structures of both compounds contain polymeric [Ca(H2O) n ]22 CB[6]∞ cations that form infinite columns; the space between them is filled with Cls- (1) and [Mo3O2S2Cl6(H2O)3]2s- (2). A new (H7O3)2(H5O2)× [Mo3S4Cl6.25Br0.25(H2O)2](C36H36N24O12)·CH2Cl2·6H2O complex (3) is also obtained and structurally characterized.  相似文献   

14.
31P, 19F, 1H NMR is used to study fluorophosphatometalates of the composition MHfF2PO4·0.5H2O (M = Rb, Cs) and CsMe2F6PO4·4H2O (Me = Zr, Hf). The data obtained indicate the isostructurality of compounds in each of these two groups. The lines in the NMR spectra are assigned. Assumptions about the character of the bond of PO4 groups and F atoms with Me are made and schemes of the crystal structure of fluorophosphatometalates are proposed. The occurrence of several types of crystallization water characterized by different bond strengths and energy barriers of the diffusion motion is found.  相似文献   

15.
[TMPA]4[Si8O20] · 34 H2O ( 1 ) and [DDBO]4[Si8O20] · 32 H2O ( 2 ) have been prepared by crystallization from aqueous solutions of the respective quaternary alkylammonium hydroxide and SiO2. The crystal structures have been determined by single-crystal X-ray diffraction. 1 : Monoclinic, a = 16.056(2), b = 22.086(6), c = 22.701(2) Å, β = 90.57(1)° (T = 210 K), space group C2/c, Z = 4. 2 : Monoclinic, a = 14.828(9), b = 20.201(7), c = 15.519(5) Å, β = 124.13(4)° (T = 255 K), space group P21/c, Z = 2. The polyhydrates are structurally related host-guest compounds with three-dimensional host frameworks composed of oligomeric [Si8O20]8? anions and H2O molecules which are linked via hydrogen bonds. The silicate anions possess a cube-shaped double four-ring structure and a characteristic local environment formed by 24 H2O molecules and six cations (TMPA, [C8H20N2]2+, or DDBO, [C8H18N2]2+). The cations themselves reside as guest species in large, irregular, cage-like voids. Studies employing 29Si NMR spectroscopy and the trimethylsilylation method have revealed that the saturated aqueous solutions of 1 and 2 contain high proportions of double four-ring silicate anions. Such anions are also abundant species in the saturated solution of the heteronetwork clathrate [DMPI]6[Si8O18(OH)2] · 48.5 H2O ( 3 ) with 1,1-dimethylpiperidinium (DMPI, [C7H16N]+) guest cations.  相似文献   

16.
Twenty-five zirconium (hafnium) fluoride compounds have been synthesized at room temperature in the systems MO2-H2SO4-M′nA(HF)-H2O (M = Zr (Hf); M′ = Na, K, Rb, Cs, NH4; A = F, SO4) and their X-ray luminescence spectra (luminescence wavelengths and relative intensities) have been measured. The X-ray luminescence of the compounds has been considered as a function of the composition (cations, anions, water content) and different structural factors (CNs, polyhedra, H-bonds). Ammonium compounds do not luminesce, and sodium fluorozirconates and heptafluorozirconates are weakly luminescing. Hexafluorozirconates M2Zr(Hf)F6 (M= K, Rb, Cs) and M5Zr4F21 · 3H2O (M = Rb, Cs), as well as oxofluorozirconate Rb2Zr3OF12, are strongly luminescing compounds.  相似文献   

17.
Single crystals of fluoride hydrates Mn3F8 · 12 H2O and AgMnF4 · 4 H2O have been prepared and characterized by X-ray methods. Mn3F8 · 12 H2O crystallizes in the space group P1 (a = 623.0(3), b = 896.7(4), c = 931.8(4) pm, α = 110.07(2)°, β = 103.18(2)°, γ = 107.54(2)°, Z = 1); AgMnF4 · 4 H2O crystallizes in the space group P21/m (a = 700.9(2), b = 726.1(1), c = 749.4(3) pm, β = 107.17(3)°, Z = 2). Both structures contain Jahn-Teller-distorted [Mn(H2O)2F4]? anions as well as crystal water molecules and exhibit a complex hydrogen bond network between anions and cations, i. e. [Mn(H2O)6]2+ for the first and a polymeric [Ag(H2O)2]? cation for the second compound.  相似文献   

18.
Mixtures of 4‐carboxypyridinium perchlorate or 4‐carboxypyridinium tetrafluoroborate and 18‐crown‐6 (1,4,7,10,13,16‐hexaoxacyclooctadecane) in ethanol and water solution yielded the title supramolecular salts, C6H6NO2+·ClO4·C12H24O6·2H2O and C6H6NO2+·BF4·C12H24O6·2H2O. Based on their similar crystal symmetries, unit cells and supramolecular assemblies, the salts are essentially isostructural. The asymmetric unit in each structure includes one protonated isonicotinic acid cation and one crown ether molecule, which together give a [(C6H6NO2)(18‐crown‐6)]+ supramolecular cation. N—H...O hydrogen bonds between the protonated N atoms and a single O atom of each crown ether result in the 4‐carboxypyridinium cations `perching' on the 18‐crown‐6 molecules. Further hydrogen‐bonding interactions involving the supramolecular cation and both water molecules form a one‐dimensional zigzag chain that propagates along the crystallographic c direction. O—H...O or O—H...F hydrogen bonds between one of the water molecules and the anions fix the anion positions as pendant upon this chain, without further increasing the dimensionality of the supramolecular network.  相似文献   

19.
The structures of orthorhombic bis[pentaammineaquacobalt(III)] tetra‐μ2‐fluorido‐tetradecafluoridotrizirconium(IV) hexahydrate (space group Ibam), [Co(NH3)5(H2O)]2[Zr3F18]·6H2O, (I), and bis[hexaamminecobalt(III)] tetra‐μ2‐fluorido‐tetradecafluoridotrizirconium(IV) hexahydrate (space group Pnna), [Co(NH3)6]2[Zr3F18]·6H2O, (II), consist of complex [Co(NH3)x(H2O)y]3+ cations with either m [in (I)] or and 2 [in (II)] symmetry, [Zr3F18]6− anionic chains located on sites with 222 [in (I)] or 2 [in (II)] symmetry, and water molecules.  相似文献   

20.
The calcium salts Ca2P2O6 · 2H2O ( 1 ) and [Ca(H2O)3(H2P2O6)] · 0.5(C12H24O6) · H2O ( 2 ) were prepared and structurally characterized by single‐crystal X‐ray diffraction. Compound 1 crystallizes in the orthorhombic space group Pbca and compound 2 in the monoclinic space group P21/n. The crystal structure of compound 1 consists of chains of edge‐sharing [CaO7] polyhedra linked by hypodiphosphate(IV) anions to form a three‐dimensional network. The crystal structure of compound 2 consists of alternated layers of crown ether and water molecules and respective ionic units. Within the layers of ionic units the Ca2+ cations are octahedrally coordinated by three monodentate dihydrogenhypodiphosphate(IV) anions and three water molecules. The IR/Raman spectra of the title compounds were recorded and interpreted, especially with respect to the [P2O6]4– and [H2P2O6]2– groups. The phase purity of 2 was verified by powder diffraction measurements.  相似文献   

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