New Heteropolytungstates Incorporating Dioxouranium(VI). Derivatives of α-[SiW9O34]10−, α-[AsW9O33]9−, γ-[SiW10O36]8−, and [As4W40O140]28−

Reaction of uranium salts with several lacunary polyoxotungstate anions yields four new heteropolyanion assemblies in which the uranium atoms occupy pentagonal bipyramidal coordination polyhedra. Treatment of A,-[SiW₉O₃₄]^10– with UO₂(NO₃)₂ leads to Na₁₄[Na₂(UO₂)₂(SiW₉O₃₄)₂]38H₂O (1, Monoclinic, P2₁/c, a=16.5719(8) Å, b=14.1689(7) Å, c=21.2528(10) Å, =111.6670(10)°, V=4786.6(4) ų, Z=2) which proves to be isostructural with the analogous derivative of [PW₉O₃₄]^9– reported previously. Solutions of 1 exhibit the 5-line W-NMR spectrum expected for the structure of C _i point symmetry. The salt (NH₄)₁₇[(UO₂)₃(H₂O)₄As₃W₂₆O₉₄]16H₂O (2, Orthorhombic, Pnma, a=40.1747(2) Å, b=18.25840(10) Å, c=18.0817(2) Å, V=13263.4(2) ų, Z=4) was isolated in 64% yield from a reaction of UO₂(NO₃)₂ with B,-[AsW₉O₃₃]^9–. The structure of the anion in 2 has C _s symmetry and contains one -AsW₉O₃₃ and two novel -AsW₈O₃₀ units linked by the UO²⁺ ₂ groups; an additional WO₆ links the two AsW₈ fragments. Spectrophotometric titration of UCl₄ with the sodium salt of [As₄W₄₀O₁₄₀]^28– indicated the formation of a 4:1 U:As₄W₄₀ complex. During attempts to isolate a crystalline product from this reaction the uranium became oxidized and a guanidinium salt of [Na(UO₂)₃(OH)(H₂O)₆As₄W₄₀O₁₄₀(WO)]^18– (3, Orthorhombic, Fdd2, a=54.848(3) Å, b=80.809(4) Å, c=20.2874(2) Å, V=89919(7), Z=16) was isolated. The partially disordered structure of 3 shows the S₂ and adjacent sites of the lacunary As₄W₄₀ anion to be occupied by three UO₅ and one WO₅ polyhedra. A tetrameric assembly of -SiW₁₀ units linked by UO²⁺ ₂ groups occurs in [{M(OH₂)}₄(UO₂)₄(OH)₂(SiW₁₀O₃₆)₄]^22– (lithium salt, M=Na, 4a, tetragonal, P4₂/nmc, a=b=26.5285(2) Å, c=15.0463(2) Å, V=10589.0(2) ų, Z=2; sodium-potassium salt, M=K, 4b, orthorhombic, Fddd, a=24.180(5) Å, b=31.696(6) Å, c=58.012(12) Å, V=44460(15) ų, Z=8). Tungsten-183 NMR spectra show the slow transformation of the expected 5-line (1:1:1:1:1) spectrum of 4a to a new species giving a 6-line spectrum (2:2:2:1:2:1). The latter complex has not been successfully isolated.     

Dimerization in Acetonitrile of [H6PMo9O34]3− into [P2Mo18O62]6−: Structural Characterization of the Tetrabutyl Ammonium Salt

The trivacant heteropolyanion A-α[PMo₉O₃₁(OH₂)₃]³⁻ spontaneously dimerizes in acetonitrile to form the Dawson complex [P₂Mo₁₈O₆₂]⁶⁻. A rapid new quantitative preparation of the sodium salt of this Dawson complex is described. In addition, the structure of TBA₅[HP₂Mo₁₈O₆₂] is given and the featuring data compared with the isomorphous sodium salt (space group C2/c).

Cerium(III) Complexes with Lacunary Polyoxotungstates. Synthesis and Structural Characterization of a Novel Heteropolyoxotungstate Based on α-[SbW9O33]9− Units

Several cerium(III) complexes with lacunary polyoxotungstates -B-XW₉O^9– ₃₃ (X=As^III, Sb^III) and W₅O^6– ₁₈, have been synthesized and characterized by single-crystal X-ray analysis, elemental analysis and IR spectroscopy. The X-ray analysis of Na₂₅[Ce(H₂O)₅As₄W₄₀O₁₄₀]63H₂O (1) reveals the framework of the well-known [As₄W₄₀O₁₄₀]^28– anion with a {Ce(H₂O)₅}³⁺ unit in the central site S1. The anion in (NH₄)₁₉[(SbW₉O₃₃)₄{WO₂(H₂O)}₂Ce₃(H₂O)₈(Sb₄O₄)]48H₂O (2) consists of a tetrahedral assembly of four -B-Sb^IIIW₉O^9– ₃₃ units connected by two additional six-coordinate tungsten atoms, three nine-coordinate monocapped square-antiprismatic cerium atoms and a Sb₄O₄ cluster. The Ce^III center in the [Ce(W₅O₁₈)₂]^9– anion in Na₉[Ce(W₅O₁₈)]NaCl30H₂O (3) displays the square-antiprismatic environment observed in all complexes of the type [Ln(W₅O₁₈)₂] ^n–.     

Subtle difference of [SiMo12O40]4− and [PMo12O40]3− inducing two new distinct Keggin-Ag-(1H-Pyrazole) compounds

Two new inorganic-organic hybrid compounds based on α-Keggin clusters and Ag-(1H-Pyrazole) subunits, [AgL₂]₄[SiMo₁₂O₄₀] (1) and [AgL₂]₃[PMo₁₂O₄₀] (2) (L = pyrazole), have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction. In 1, there are two kinds of chains, the chains linked by two [AgL₂]⁺ clusters and the other linked only by one [AgL₂]⁺, which further connect by sharing [SiMo₁₂O₄₀]^4? anions to construct a 2-D layer. In 2, four-supporting [PMo₁₂O₄₀]^3? anions are fused by [Ag(1)L₂]⁺ subunits to form a 1-D chain. Through weak interactions of Ag?O (3.091 Å) a 2-D supramolecular layer is constructed. Additionally, the electrochemical properties of title compounds and the photocatalytic properties of 2 have been studied.     

Two new organic-inorganic hybrid compounds induced by γ-[Mo8O26]4− and [PMo12O40]3−

Two new organic–inorganic hybrid compounds, [Cu^II(btb)_1.5(γ-Mo₈O₂₆)_0.5(H₂O)]·2H₂O (1) and [Cu^II₂(btb)₄(PMo^VMo^VI₁₁O₄₀)]·2H₂O (2) (btb = 4-butyl-1,4-bis(1,2,4-triazole), have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, IR spectra and elemental analyses. In 1, there exists a ladder-like metal-organic chain with the bidentate [γ-Mo₈O₂₆]^4? anions inserting into the grids. Adjacent chains share the same Cu-btb lines of the ladder to form a 2-D layer. Compound 2 also has a ladder-like metal-organic chain. The tetradentate [PMo₁₂O₄₀]^3? anions embed in the grids. The same Cu-btb line is shared by adjacent chains to build a 2-D layer. The btb ligands link adjacent layers to form a 3-D framework. Moreover, we also have investigated the electrochemical and photocatalytic properties of 1 and 2.     

Lacunary Derivative [HPW9O34]8− as Reusable and Active Catalyst for Alcohol Oxidation in Water

Abstract

An effective and reusable catalytic system for the oxidation of alcohols was developed based on ?-Na₈HPW₉O₃₄. The oxidation was conducted in water using hydrogen peroxide as oxidant. Good yields of ketones were obtained in oxidation of secondary alcohols, and the catalyst was recycled 10 times without obvious loss in activity.     

Synthesis and structure of antimony iodide complexes: [Ph3MeP] + 2 [SbI5]2−, [Ph3MeP] + 3 [Sb3I12]3−·Me2C=O, [Ph3MeP] + 3 [Sb3I12]3−, and [Ph3MeP] + 3 [Sb2I9]3−

Complexes with antimony-containing anions, [Ph₃MeP] ₊ ² [SbI₅]^2? (I), [Ph₃MeP] ₊ ² [Sb₃I₁₂]^3? (II), [Ph₃MeP] ₊ ³ [Sb₃I₁₂]^3? · Me₂C=O (III), and [Ph₃MeP] ₊ ³ [Sb₂I₉]^3? (IV), were synthesized by reacting triphenylmethylphosphonium iodide with antimony iodide. The central atom in the cations of the complexes has a distorted tetrahedral coordination. In the trinuclear anions of complexes II and III, each of the terminal SbI₃ groups is bound to the central Sb atom through two μ₂- and one μ₃ iodine bridges (SbSbSb angles are 103.0° and 102.2°, respectively). In the binuclear anion of complex IV, antimony atoms are linked with each other via three bridging iodine atoms.     

The vibrational spectra of [Nb(O2)F5]2−

The Raman and i.r. spectra of solid K₂[Nb(O₂)F₅] · H₂O and the Raman spectrum of its aqueous solution are reported, and assignments for the vibrations of the anion proposed.     

Synthesis and Study of Tetraamminenickel 9-Molybdomanganate [Ni(NH3)4] · H4[MnMo9O32] · 6H2O

Tetraamminenickel 9-molybdomanganate [Ni(NH₃)₄] · H₄[MnMo₉O₃₂] · 6H₂O (zbdI) has been synthesized and studied by thermogravimetry, IR spectroscopy, and X-ray powder diffraction analysis. The crystals of compound I are monoclinic: a = 11.5961 Å, b = 11.1609 Å, c = 8.7200 Å, β = 109.23°, V = 1065.59 ų, ρ_calcd = 3.067 g/cm³, Z = 1.     

铁液中[Ce]-[O]-[S]沉淀图及其应用

选用近期实验所测较为准确的稀土-氧、稀土-硫、稀土-氧-硫体系的热力学数据建立了纯铁液中的[Ce]-[O]-[S]空间沉淀图。应用热力学理论计算了铁液中氧硫活度与生成的稀土夹杂物间的定量关系。确定了铁水初始氧硫活度与生成稀土夹杂物类型的关系,并验证了理论计算结果。     

[6O]富勒烯的化学修饰

对近年来一些新的[60]富勒烯的化学修饰方法进行了综述。参考文献76篇。     

The 20-Tungsto-4-Tellurate(IV) [H2Te4W20O80]22− and the 15-Tungstotellurate(IV) [NaTeW15O54]13−

The 20-tungsto-4-tellurate(IV) polyanion [H₂Te₄W₂₀O₈₀]^22? (1) has been synthesized and isolated in the form of its hydrated sodium salt Na₂₂[H₂Te₄W₂₀O₈₀]·64H₂O (Na-1). Na-1 has been characterized in the solid state by FTIR and TGA. Single-crystal X-ray diffraction analysis revealed that Na-1 crystallizes in the triclinic space group P ${\bar 1}The 20-tungsto-4-tellurate(IV) polyanion [H₂Te₄W₂₀O₈₀]²²⁻ (1) has been synthesized and isolated in the form of its hydrated sodium salt Na₂₂[H₂Te₄W₂₀O₈₀]·64H₂O (Na-1). Na-1 has been characterized in the solid state by FTIR and TGA. Single-crystal X-ray diffraction analysis revealed that Na-1 crystallizes in the triclinic space group P , with a = 12.741(2) ?, b = 16.842(3) ?, c = 17.197(4) ?, α = 93.961(10)°, β = 107.466(8)°, γ = 108.548(8)°, V = 3281.5(11) ?³ and Z = 1. The polyanion 1 comprises two [HTe₂W₁₀O₄₀]¹¹⁻ fragments, connected through Te−O–W μ₂-oxo bridges, and each containing a pair of face-shared WO₆ octahedra. Furthermore, the 15-tungstotellurate(IV) polyanion [NaTeW₁₅O₅₄]¹³⁻ (2) was synthesized and crystallized as a sodium salt in the orthorhombic space group Pccn, with a = 11.8841(5) ?, b = 20.8934(11) ?, c = 31.801(2) ?, V = 7896.3(7) ?³ and Z = 4. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Dedicated to Professor C. N. R. Rao on the occasion of his 75th birthday     

Synthesis and Structure of Two Keggin-Type Heteropolyanions: [VMo12O40]3n− n (1) and [H3PMoVMoVI 11O40]1− (2)

Two Keggin-type heteropolyanions were synthesized and characterized by X-ray crystal structure and elemental analysis as well as infrared spectroscopy. Both K₃[VMo₁₂O₄₀]19H₂O (1) and [N _i (H₂O)₆][H₃PMo^VMo^VI ₁₁O₄₀]₂30 H₂O (2) were prepared in aqueous solution. Compound 1 crystallized in the space group Pm-3m, a=10.6513(1) Å, V=1208.4(3) ų, Z=1. Compound 2 crystallized in the space group R-3 with a=b=13.9669(2) Å, c=42.0075(5) Å, V=7096.71(2) ų, Z=3. The compound 1 contains a {K₆VMo₁₂O₄₀} group in which six potassium ions form a regular {K₆} octahedron. The heteropolyanion [VMo₁₂O₄₀]^3– was capped by six potassium ions and enclosed by {K₆} octahedron. A three-dimensional structure was formed by the buildup of {K₃[VMo₁₂O₄₀]} _n . Compound 2 contains a one-electron reduced heteropolyanion [H₃PMo^VMo^VI ₁₁O₄₀]^1–. Ni²⁺ coordinated by six water molecules as the counter cation balances the negative charge of the molecule.     

The pH-controlled[2]or [3]pseudorotaxanes based on stilbene dye SD⊂CB[7]

We studied characteristics of [2] or [3]pseudorotaxanes based on stilbene dye SD?CB[7] . In neutral or weak alkaline conditions, SD could be encapsulated inside the stilbene site of CB[7] with 1:1 stoichiometry, whereas, with the pH changing to acidity, the hydrogen bonding between the carboxyl group and the carbonyl of CB[7] maked another CB[7] molecule include into hexanoic acid site, these processes were confirmed by fluorescence spectra,UV–Vis spectra and 1H NMR.     

Synthesis and Structure of [Co2Bi2(α or β-Β-CoW9O34)2]14− Isomers and Their Catalytic Water Oxidation

A new sandwich-type complex based [α-Β-CoW₉O₃₄]^12? as ligand, Na₉H₅[Co₂Bi₂(α-Β-CoW₉O₃₄)₂]·54H₂O 2, has been synthesized and characterized structurally by elemental analysis, single-crystal X-ray diffraction, IR, XRD and TG. Structural analysis indicates that the anion of 2 is isomeric with that of Na₁₄[Co₂Bi₂(β-Β-CoW₉O₃₄)₂]·48H₂O 1. It is constructed through sandwiching Bi^III and Co^II ions with [α-B-Co^IIW₉O₃₄]^12? anions. Cyclic voltammetry experiments are carried out in 50 mM sodium phosphate buffer (pH = 7.4) containing 1 mM [Ru(bpy)₃]²⁺ solution. It is found that both 1 and 2 exhibit catalytic activity of the electrochemical oxidation of H₂O into O₂. Visible-light-induced catalytic activity of 1 and 2 are investigated by using [Ru(bpy)₃]²⁺ as a photosensitiser and S₂O₈ ^2? as a sacrificial electron acceptor. In 40 min, 16.8 and 5.3 μmol of O₂ are produced for 1 and 2 respectively.     

Diversity of Functionalized Germanium Zintl Clusters: Syntheses and Theoretical Studies of [Ge9PdPPh3]3− and [Ni@(Ge9PdPPh3)]2−

Abstract  A new Zintl cluster [Ge₉PdPPh₃]³⁻ has been isolated as (2,2,2-crypt)K⁺ salt through the reaction of K₄Ge₉ and Pd[PPh₃]₄ in ethylenediamine solutions and characterized via single-crystal X-ray crystallography. The as-prepared bimetallic [Ge₉PdPPh₃]³⁻ cluster could successfully trap a nickel atom to form a trimetallic cluster [Ni@(Ge₉PdPPh₃)]²⁻. The coordination of Ge₉ ⁴⁻ by PdPPh₃ induces a one-electron oxidation and encapsulation of the Ni atom into the Ge₉ ³⁻ cage leads to a further one-electron oxidation and a geometry transformation from C_4v (nido) to C_3v (closo). Graphical Abstract   Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.

The bis(ethylene)-dithiotetrathiafulvalene radical salt of [PVMo11O40]4−

The charge transfer salt, (ET)5PVMo11O40·2H2O [ET=bis(ethylene)-dithiotetrathiafulvalene], was prepared by reducing the diamagnetic molybdovanadophosphoric heteropoly acid (H4PMo11VO40·nH2O, HMVP) with the organic donor ET. The u.v.-vis spectrum of the complex shows an electronic transfer band at 900nm. The i.r. and Raman spectra suggest that the ET donor molecules are all completely ionized. Magnetic measurements indicate the presence of antiferromagnetic interactions in the ET organic sublattice. The e.s.r. spectrum exhibits a VIV signal with g=1.9718 and a=57.5cm–1. Over the measured temperature range (75–300K), no significant interaction between the paramagnetic anion and the organic radical cation is observed.