六钨酸四丁基铵盐和异丙醇体系的催化氧化反应的ESR研究Ⅰ.

本文研究了六钨酸四丁基铵盐在紫外光辐照的条件下催化氧化异丙醇为丙酮的反应。采用自旋捕捉技术与电子自旋共振相结合的方法,在位检测到氧化反应过程中有活泼自由基中间体产生,并观察到光电流产生。文中对六钨酸四丁基铵盐的催化反应机理进行了讨论。     

六钨酸四丁基铵盐和异丙醇体系的催化氧化反应的ESR研究Ⅱ.

近年来,关于同多酸、杂多酸及其盐类的光催化研究报道较多^[1,2],而用电解方法研究它们的催化反应则很少见报道^[3]。本文采用恒电位电解条件,将六钨酸四丁基铵中的钨(Ⅵ)还原成钨(Ⅴ),再考察其催化异丙醇的氧化反应。结果表明,[W₆O₁₉]^2-非但具有光化学活性,也具有电化学活性^[4]。我们用电子自旋共振和自旋捕捉相结合的方法,检测到反应过程中产生的自由基中间体。用计算机模拟方     

六钨酸四丁基铵盐和异丙醇体系的催化氧化反应的ESR研究Ⅱ.

前言 近年来,关于同多酸、杂多酸及其盐类的光催化研究报道较多,而用电解方法研究它们的催化反应则很少见报道。本文采用恒电位电解条件,将六钨酸四丁基铵中的钨(Ⅵ)还原成钨(Ⅴ),再考察其催化异丙醇的氧化反应。结果表明,[W_6O_(19)]~(2-)非但具有光化学活性,也具有电化学活性。我们用电子自旋共振和自旋捕捉相结合的方法,检测到反应过程中产生的自由基中间体。用计算机模拟方法确定其结构,因而对机理的讨论更为清楚。     

六钨酸盐为模板的三维网状超分子化合物[La2(DNBA)4(DMF)8][W6O19]的合成和晶体结构

A new three-dimensional (3D) lanthanide-aromatic monocarboxylate dimer supramolecular network [La₂(DNBA)₄(DMF)₈][W₆O₁₉] (DNBA=3,5-dinitrobenzoate, DMF=dimethylfomamide) was synthesized using hexatungstate anion (W₆O₁₉^2-) as template. The crystal structure of the title compound has been determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a=1.334 54(18) nm, b=1.387 52(19) nm, c=1.426 06(19) nm, α=102.189(2)°, β=101.023(2)°, γ=116.349(2)°, V=2.187 2(5) nm³, D_c=2.364 g·cm^-3, Z=1, F(000)=1 453.40. The single crystal structure reveals that two La(Ⅲ) ions are bridged by four 3,5-dinitrobenzoate anions as asymmetrically bridging ligands, leading to dimeric cores, [La₂(DNBA)₄(DMF)₈]²⁺; [La₂(DNBA)₄(DMF)₈]²⁺ groups are joined together by π-π stacking interaction between the aromatic groups to form a two-dimensional grid-like network; the 2D supramolecular layers are further extended into 3D supramolecular network with a 1D box-like channels by hydrogen bonding interactions, in which hexatungstate polyanions reside. CCDC: 284694.     

四丁基铵钨多酸[TBA]2[W6O19]:无溶剂条件下通过不对称汉斯反应快速合成聚氢化喹啉的新型可重复使用的非均相催化剂（英文）

A novel, efficient, and environmentally friendly method for the synthesis of polyhydroquinoline derivatives by a one‐pot, four‐component unsymmetrical Hantzsch condensation of dimedone, aldehydes, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of tetrabutylammonium hexatungstate [TBA]2[W6O19] under solvent‐free conditions has been developed. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and considerable catalytic activity was still achieved after the fifth run.     

六钨酸盐为模板的三维网状超分子化合物[La2(DNBA)4(DMF)8][W6O19]的合成和晶体结构

0 Introduction polyoxometalates (POMs), in addition to their im- portance in catalysis, biochemical separation and medicinal chemistry, play an important role for the design of new materials with novel electronic, magnet- ic and topological properties[1￣…     

六钨酸四丁基铵盐和异丙醇体系的催化氧化反应的ESR研究Ⅰ.

本文研究了六钨酸四丁基铵盐在紫外光辐照的条件下催化氧化异丙醇为丙酮的反应。采用自旋捕捉技术与电子自旋共振相结合的方法,在位检测到氧化反应过程中有活泼自由基中间体产生,并观察到光电流产生。文中对六钨酸四丁基铵盐的催化反应机理进行了讨论。     

Darstellung,Schwingungsspektren und Kristallstrukturen von [(Ph3P)2N]2[(W6Cl)I] · 2 Et2O · 2 CH2Cl2 und [(Ph3P)2N]2[(W6Cl)(NCS)] · 2 CH2Cl2

Synthesis, Crystal Structures, and Vibrational Spectra of [(Ph₃P)₂N]₂[(W₆Cl )I ] · 2 Et₂O · 2 CH₂Cl₂ and [(Ph₃P)₂N]₂[(W₆Cl )(NCS) ] · 2 CH₂Cl₂ By treatment of [(W₆Cl)I]^2– with (SCN)₂ in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(W₆Cl)(NCS)]^2– is formed. X‐ray structure determinations have been performed on single crystals of [(Ph₃P)₂N]₂[(W₆Cl)I] · 2 CH₂Cl₂ · 2 Et₂O ( 1 ) (triclinic, space group P1, a = 10.324(5), b = 14.908(3), c = 17.734(8) Å, α = 112.78(2)°, β = 99.13(3)°, γ = 92.02(3)°, Z = 1) and [(Ph₃P)₂N]₂[(W₆Cl)(NCS)] · 2 CH₂Cl₂ ( 2 ) (triclinic, space group P1, a = 11.115(2), b = 14.839(2), c = 17.036(3) Å, α = 104.46(1)°, β = 105.75(2)°, γ = 110.59(1)°, Z = 1). The thiocyanate ligands of 2 are bound exclusively via N atoms with W–N bond lengths of 2.091–2.107 Å, W–N–C angles of 173.1–176.9° and N–C–S angles of 178.1–179.3°. The vibrational spectra exhibit characteristic innerligand vibrations at 2067–2045 (ν_CN), 879–867 (ν_CS) and 490–482 (δ_NCS). Based on the molekular parameters of the X‐ray determination of 1 the vibrational spectra of the corresponding (n‐Bu₄N) salt of 1 are assigned by normal coordinate analysis. The valence force constants are f_d(WW) = 1.61, f_d(WI) = 1.23 and f_d(WCl) = 1.10 mdyn/Å.     

Synthesis and Crystal Structure of di p Methyl pyridinium p methylpyridinidine Hexatungstate

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