Synthesis and characterization of one- to three-dimensional compounds composed of paradodecatungstate-B cluster and transition metals as linkers

Three new extended frameworks built from paratungstate and transition metals have been synthesized and characterized. In the compound Na₈[{Cd (H₂O)₂}(H₂W₁₂O₄₂)]·32H₂O (1), two neighboring paratungstate-B ions [H₂W₁₂O₄₂]¹⁰⁻ are linked by [Cd(H₂O)₂]²⁺ units, leading to the formation of infinite one-dimensional (1D) anion chain [{Cd(H₂O)₂}(H₂W₁₂O₄₂)]_n⁸ⁿ⁻. The anion [{Co(H₂O)₃}{Co(H₂O)₄}(H₂W₁₂O₄₂)]_n⁶ⁿ⁻ of the compound Na₆[{Co(H₂O)₃}{Co(H₂O)₄}(H₂W₁₂O₄₂)]·29H₂O (2) shows a layer-like (2D) structure in which paratungstate-B units are linked by CoO₆ octahedra, while the anion [{Co(H₂O)₃}₃(H₂W₁₂O₄₂)]_n⁴ⁿ⁻ of the compound (H₃O⁺)₃[{Na(H₂O)₄}{Co(H₂O)₄}₃(H₂W₁₂O₄₂)]·24.5H₂O (3) is a three-dimensional (3D) anionic polymer that consists of paratungstate-B units linked by CoO₆ octahedra. Compound 3 can reversibly adsorb and desorb water molecules leading to the color reversibly change from pink to violet. The preliminary magnetic measurement and electrochemical properties of compounds are performed. The crystal structure of unexpected product Na₄[NiW₆O₂₄H₆]·13H₂O (4) is described here for the rare report of crystal structure information on the Anderson-type polyoxotungstate which has nickel as a heteroatom.     

Syntheses,Structures and Magnetic Properties of Three New Extended Iron‐containing Heteropolytungstates

Three new extended iron‐containing heteropolytungstates were synthesized and structurally characterized: K₆[{Fe^II(H₂O)₄}₂(H₂W₁₂O₄₂)]·15H₂O ( 1 ), Na₅[{Fe(H₂O)₃}₂{Fe(H₂O)₄}_0.5(H₂W₁₂O₄₂)]·30H₂O ( 2 ) and (H₃O)⁺₂[{Fe(H₂O)₄Fe(H₂O)₃}₂(H₂W₁₂O₄₂)]·20H₂O ( 3 ). 1 and 3 crystallize in the monoclinic system, space group P2₁/n with a = 14.9967(5), b = 10.3872(3), c = 18.8237(6)Å, β = 93.407(1)°, V = 2927.1(2)ų and D_c = 4.151 g cm^—3 for 1 , and space group P2₁/c with a = 12.1794(4), b = 22.4938(4), c = 11.6941(3) Å, β = 105.731(2)°, V = 3083.7(1) ų, and D_c = 4.043 g cm^—3 for 3 . 2 is triclinic, space group P1¯, with a = 12.121(2), b = 12.426(3), c = 13.247(3)Å, α = 68.33(3), β = 71.33(3), γ = 71.44(3)°, V = 1710.7(6)ų and D_c = 3.735 g cm^—3. In all cases, the structures are based on paradodecatungstate polyoxoanions, which are linked by iron ions into chains, layers and a three‐dimensional structure for 1 , 2 and 3 , respectively.     

A pure inorganic 2-D framework based on paradodecatungstate and Mn2+ ions: syntheses,structure, and properties

A pure inorganic 2-D framework based on paradodecatungstate polyanions and [Mn(H₂O)_n]²⁺ (n = 2, 3) ions, Na₁₀{[Mn(H₂O)₃]₂[H₂W₁₂O₄₂]}{[Mn(H₂O)₃]₂[Mn(H₂O)₄][H₂W₁₂O₄₂]}·56H₂O (1), has been synthesized and characterized by IR spectra, UV–vis spectra, thermogravimetric analysis (TGA), single-crystal X-ray diffraction, and magnetic measurements. Single-crystal X-ray diffraction analysis indicates that [H₂W₁₂O₄₂]^10? in 1 is a tetradentate ligand and coordinates to four [(Mn(H₂O)₃]²⁺ cations through terminal oxygens to form manganese doubly bridged 1-D chains, which are further linked through [Mn(H₂O)₄]²⁺ ions into a 2-D layer. The catalytic activities of 1 are tested in the selective oxidation of benzyl alcohol to benzaldehyde with 30% aqueous H₂O₂ as oxidant in toluene, exhibiting 90% conversion and 93% selectivity. Magnetic studies indicate that weak antiferromagnetic couplings exist between the Mn(II) ions in 1.     

由Mn2+连接仲钨酸盐[H2W12O42]10-构成一维梯型链状多金属氧酸盐

利用Na2WO4·2H2O与MnCl2反应, 合成了一个结构新颖的一维梯型链状的多金属钨酸盐K6[Mn2(H2O)8(H2W12O42)]·14.5H2O(1), 并通过元素分析、红外光谱、热重分析、紫外光谱、电化学和X射线单晶衍射对其进行了表征. 结果表明, 该化合物属于单斜晶系, P2(1)/n空间群，晶胞参数a=1.5042(3) nm, b=1.0462(2) nm, c=1.8843(4) nm, β=93.55(3)°, V=2.9594(10) nm3, Z=2. 该化合物具有由同多酸盐和Mn2+离子构筑的一维梯型链状结构.