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.     

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.     

A series of new organic–inorganic compounds templated by the [SiW12O40]4− polyanion

Two couples of new compounds templated by the polyanion [SiW₁₂O₄₀]^4?,[Hbix][Cu^I(bix)]₃[SiW₁₂O₄₀]·4H₂O (1) and [Cu^II(H₂O)(Hbix)₂(bix)]₂[Cu^II(H₂O)₂(Hbix)₂(bix)][SiW₁₂O₄₀]₃·4H₂O (2) (bix = 1,4-Bis(imidazol-1-ylmethyl)benzene), [Cu^I(bbi)]₄[SiW₁₂O₄₀]·2H₂O (3) and [Cu^II(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 Cu^II. In compound 1, the higher ratio of bix results in the transformation of the Cu^II to Cu^I, the [SiW₁₂O₄₀]^4? templates direct the Cu^I–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 Cu^II–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 Cu^I–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 Cu^II–bbi coordination polymers which accommodated the SiW₁₂ templates.     

Hybrid Tungstocuprate [Cu(2,2'-bpy)3]2H4[CuW12O40]·6H2O Based on Keggin Polyoxoanion [CuW12O40]6-with CuⅡas Heteroatom

A novel hybrid tungstocuprate(Ⅱ) [Cu(2,2'-bpy)3]2H4[CuW12O40]·6H2O(2,2'-bpy=2,2'-bipyridine) was synthesized via hydrothermal method and characterized using elemental analyses, IR, UV, XPS, TG-DSC, EPR, and X-ray single crystal diffraction. The structural analysis shows that the complex consists of an unusual Keggin-type polyoxoanion [CuW12O40]6- and a pair of chiral complex cations [Cu(2,2'-bpy)3] together with four protons and six crystallization water molecules, and the Keggin polyoxoanion is connected with [Cu(2,2'-bpy)3] via multiple C-H…O hydrogen bonds resulting in a dimer.     

A new supramolecular compound based on Mn(II)-Schiff-base and Keggin-type [PMo12O40]3−

A new organometallic-inorganic hybrid compound {[Mn(L)₂]₂[PMo₁₂O₄₀][NO₃] · 4CH₃OH · 3H₂O} _n (I), where L is 1,4-bis(4-imidazolyl)-2,3-diaza-1,3-butadiene) was synthesized in situ from [PMo₁₂O₄₀]^3?, Mn²⁺ and L reaction in an H₂O-DMSO-CH₃OH mixture at room temperature, and the product was structurally characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction analysis. Compound I is constructed from alternating layers of the metal-Schiff-base cation and Keggin anions based on electrostatic forces and hydrogen bond interactions.     

Two new supramolecular compounds based on Ni(II)-Schiff-base and Keggin-type [PMo12O40]3−

Two polyoxometalate-templated nickel-Schiff-base compounds, {[Ni(L)₂]₂[PMo₁₂O₄₀][Cl] · 1.5DMF · H₂O} _n (1) and {[Ni(L)₂]₂[PMo₁₂O₄₀][Cl] · DMSO · CH₃OH · 0.5H₂O} _n (2) (where L is 1,4-bis(4-imidazolyl)-2,3-diaza-1,3-butadiene), were synthesized in situ from Ni²⁺ and L in H₂O/DMF/CH₃OH or H₂O/DMSO/CH₃OH at room temperature and characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction analysis. The results of the single-crystal X-ray diffractions suggested that both compounds have the same packing of the Ni(II)-Schiff-base cation layer and Keggin anion layer. Thermogravimetric analyses suggested that two supramolecular compounds have similar thermal stabilities based on the same packing of the cation and anion layers.     

Formation of [FeW12O40]5− under hydrothermal conditions: syntheses,crystal structures,and characterization of [Fe(2,2′-bipy)3]2[HFeW12O40] · 5H2O and (4,4′-H2bipy)6(Hpy)2(H3O)[FeW12O40]3 · 11H2O

Two supramolecular compounds based on tungstoferrate [FeW₁₂O₄₀]^5?, [Fe^II(2,2′-bipy)₃]₂[HFeW₁₂O₄₀] · 5H₂O (1), and [Hpy]₂[4,4′-H₂bipy]₆(H₃O)[FeW₁₂O₄₀]₃ · 11H₂O (2) (py = pyridine, bipy = bipyridine) were synthesized hydrothermally and characterized structurally. The hydrogen bonds between polyoxoanions and water and the edge-to-face π–π interaction between [Fe^II(2,2′-bipy)₃]²⁺ with a shortest C–C distance of 3.513 Å are the main forces to construct the 3-D architecture of 1. In 2, a 3-D supramolecular architecture is assembled by the tungstoferrate anions, protonated 4,4′-bipy cations, and water through hydrogen bonding. The variable-temperature magnetic susceptibilities indicate that 1 is paramagnetic with μ _eff corresponding to one Fe(III) with spin-only contribution, showing that Fe in the coordination cations has a +II oxidation number and low spin state.     

Single-molecule magnetism behavior of [Mn12O12(O2CR)16(H2O)4]2− salts

(PPh₄)₂[Mn₁₂O₁₂(O₂CCHCl₂)₁₆(H₂O)₄] (3) has been prepared by the two-electron reduction of [Mn₁₂O₁₂(O₂CCHCl₂)₁₆(H₂O)₄] (2) using iodide. Crystallization from CH₂Cl₂/hexanes yields a mixture of two crystal forms, 3·4CH₂Cl₂·H₂O (3a) and 36CH₂Cl₂ (3b), which are triclinic and monoclinic, respectively. They are both trapped valence 2Mn(II), 6Mn(III), 4Mn(IV). DC magnetization data for dried, unsolvated 3 in 1.80–4.00 K and 10–70 kG ranges were fit to give S=10, D=−0.28 cm⁻¹, g=2.00. Frequency-dependent out-of-phase (χ″_M) signals in AC susceptibility studies on crystalline sample of 3a and 3b combined with DC relaxation decay data were fit to the Arrhenius equation to give an effective energy barrier of U_eff=18.5 and 30.3 K, respectively. Magnetization vs. DC field sweeps on single crystals of 3a and 3b gave hysteresis loops containing steps due to quantum tunneling of magnetization (QTM). The step separations yielded ∣D∣/g values of 0.087 and 0.14 cm⁻¹, and consequently U=20 and 39 K (for g=2) for 3a and 3b, respectively, suggesting that the differences in U_eff are primarily caused by changes to D. This work demonstrates the sensitivity of the magnetic properties of [Mn₁₂]²⁻ single-molecule magnets to subtle differences in their environment.     

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.     

Hybrid Tungstocuprate [ Cu（2,2＇-bpy）3]2 H4 [ CuW12O40 ]· 6H2O Based on Keggin Polyoxoanion [CuW12O40]^6- with Cu^Ⅱ as Heteroatom

A novel hybrid tungstocuprate （ Ⅱ ） [ Cu （2,2＇-bpy） 3 ] 2 H4 [ CuW12O40 ] · 6H2O （ 2,2＇-bpy = 2,2＇-bipyfidine） was synthesized via hydrothermal method and characterized using elemental analyses, IR, UV, XPS, TG-DSC, EPR, and X-ray single crystal diffraction. The structural analysis shows that the complex consists of an unusual Keggin-type polyoxoanion [ CuW12O40 ]^6- and a pair of chiral complex cations [ Cu（2,2＇-bpy） 3 ]^＋ together with four protons and six crystallization water molecules, and the Keggin polyoxoanion is connected with [ Cu （2,2＇-bpy）3 ]^＋v/a multiple C-H…O hydrogen bonds resulting in a dimer.     

[Co（phen）3]2[PMo12O40]（OH）的水热合成及晶体结构

利用水热合成法制备了Keggin结构阴离子有机一无机复合物[Co（phen）3]2[PMo12O40]（OH）,通过元素分析,红外光谱和X射线单晶衍射等对其进行了表征．结果表明,该化合物属于单斜晶系,C2／c空间群．=1．97225（18）nm,b=1．81079（16）nm,c=2．5117（2）nm,β=100．5380（10）°,V=8．819O（14）nm^3,Z=4,R1=0．0587,wR2=0．1211．该化合物分子由一个多阴离子[PMo12O40]^3-,两个[Co（phen）3]^2＋及一个羟基组成．     

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.     

Crystal structure and properties of H3[PMo12O40] · 3C2H6O

The title compound H₃[PMo₁₂O₄₀]· 3C₂H₆O was prepared and characterized by X-ray crystallography, its i.r. spectrum, cyclic voltammetry and e.s.r. spectra. The anion of the title compound is a Keggin-type heteropoly structure based upon a central PO₄ tetrahedron surrounded by 12 MoO₆ octahedra arranged in four groups of three edge-shared octahedra Mo₃O₁₃. Weak hydrogen bonds exist between the organic solvent molecules and the heteropoly anion. The catalytic activity of the title compound was determined by the synthesis of butyl acetate. The conversion of n-BuOH reached 93.3% and the yield of MeCO₂Bu-n was 92.0% when the ratio of MeCO₂H to n-BuOH, catalyst amount, reaction time, reaction temperature were 2:1, 0.24% of the reactants (50 mg), 2.0 h and 115 120 °C, respectively.     

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.     

三维超分子化合物[Ni（DMF）6]2[SiMo12O40]·H2O的合成、晶体结构及表征

合成了一个新的三维超分子化合物[Ni（DMF）6]2[SiMo12O40]·H2O,通过红外光谱、X射线单晶衍射和热重分析等手段对其结构进行了表征．单晶结构解析结果表明,标题化合物属于三方晶系,船空间群,晶胞参数为：a=1．5902（4）nm,b=1．5902（4）nm,c=3．2281（17）nm,V=7．069（4）nm^3,Z=3,Dc=1．994g／cm^3,μ=2．032mm^-1．F（000）：4146,R1=0．0516,ωR2=0．1453．配合物中镍离子采用6配位的八面体配位构型,晶体堆积中通过多种分子间氢键作用形成三维网状结构．     

Solvent-dependent assembly of porous coordination polymers based on Keggin-type [SiW12O40]4–

Two coordination polymers (CPs) based on Keggin-type [SiW₁₂O₄₀]^4– (SiW₁₂), [Zn₂(bpy)₂(SiW₁₂O₄₀)(DMF)₈]·solvent (1) and [Zn₂(bpy)(SiW₁₂O₄₀)(DMA)₈]·2DMA (2) (bpy = 4,4′-bipyridine, DMF?=?N,N′-dimethylformamide; DMA?=?N,N′-dimethylacetamide), have been solvo-thermally synthesized and characterized by single crystal X-ray diffraction, powder X-ray diffraction, IR spectra, elemental analyses and thermogravimetric analyses. Both 1 and 2 are synthesized under similar conditions except DMF and DMA were used as the solvents for 1 and 2, respectively. Structural studies reveal that the supramolecular framework of 1 contains pumpkin-like voids, while 2 has a non-porous supramolecular framework. These results show that solvents play an important role in construction of the POM-based CPs. The luminescent properties for 1 and 2 have also been investigated.     

Three Inorganic-organic Composite Polyoxotungstates： Syntheses,Characterization and Structures of [Cu（2,2＇-bpy）2]5[α-PW11.5Cu0.5O40]·2H2O, [Co（2,2＇-bpy）2（N3）2]4H3[α-PW12O40]·3H2O and [Cu（2,2＇-bpy）2（4,4＇-bpy）]2[α-GeW12O40]-4H2O

Three new inorganic-organic composite polyoxotungstates [Cu（2,2＇-bpy）2]5[α-PW11.5Cu0.5O40]·2H2O 1, [Co（2,2＇-bpy）2（N3）2]4H3[α-PW12O40]·3H2O 2 and [Cu（2,2＇-bpy）2（4,4＇-bpy）]2[α-GeW12O40]-4H2O 3 （2,2＇-bpy = 2,2＇-bipyridine, 4,4＇-bpy = 4,4＇-bipyridine） have been hydrothermally synthesized and structurally characterized. 1 crystallizes in the orthorhombic space group Pna21 with a = 27.847（3）, b = 21.597（2）, c = 20.1179（19）A, V= 12099（2）A^3, Z= 4, GOF= 1.038, R = 0.0427 and wR = 0.1035; 2 belongs to the triclinic space group P1^- with a = 12.31150（10）, b = 16.1954（4）, c = 19.36290（10）A, α = 99.366（11）, β =105.168（8）, γ = 111.836（8）°, V = 3309.98（9）A3, Z = l, GOF = 1.024, R = 0.0739 and wR = 0.2216; and 3 crystallizes in the monoclinic space group P21/n with a = 12.858（4）, b = 20.943（6）, c = 15.598（5）A, β = 102.338（5）°, V= 4103（2）A3, Z = 2, GOF = 1.026, R = 0.0557 and wR = 0.1316. The common structural features of 1-3 are that their molecular structures all consist of a saturated a-Keggin polyoxoanion and several discrete metal-organic moieties. Intriguingly, 2 and 3 are composed of metal-organic coordination moieties with two mixed ligands.     

[α‐PW12O40]3− Immobilized on Ionic Liquid–Modified Polymer as a Heterogeneous Catalyst for Alcohol Oxidation with Hydrogen Peroxide

Ionic liquid–modified polystyrene resin beads were demonstrated to be an appropriate support for polyoxometalate. In this heterogeneous catalytic system, alcohols can be efficiently oxidized to corresponding carbonyl groups with H₂O₂ in CH₃CN. The catalyst can be easily recovered by filtration and recycled without apparent loss of catalytic performance.     

杂多阴离子[GeMo12O40]4-α/β异构体的密度泛函研究

采用密度泛函方法，在DND基组水平上，对[GeMo12O40]^4-杂多阴离子最常见的α和β异构体进行了几何构型优化，得到了与X射线晶体衍射实验结果相一致的结构参数，并在此基础上进行了振动频率分析，得到了杂多阴离子的电子结构、热力学特性和振动光谱，通过定义α，β异构体异构化反应的Gibbs函变△Gα-β与温度的关系，研究了这两种异构体的相对稳定性．结果表明：低温时α异构体更稳定，高温时β异构体更稳定些，550K左右为转变点．振动频率分析得到2种异构体的最强峰位于4个频率位置，分别指认为vax(Mo-Od)，vas(Mo-Od)，vas(Mo-Oc-Mo)，vas(Ge-Oa)，vas(Mo-Ob-Mo)振动，与红外光谱(IR)的特征振动峰相对应，观察到了特征频率的振动模式，从理论计算角度说明了Rocchiccioli—Deltcheff关于振动模式的设想是合理的．