Synthesis and Molecular Design of Novel Modified-Heteropolyanions Containing Multicenter Active Sites

含多中心活性位点的新型改性杂多阴离子的合成与分子设计

• 批准号: 10640552
• 负责人: NOMIYA Kenji
• 金额: $ 1.98万
• 依托单位: Kanagawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10640552/
• 关键词: Modified Polyoxometalates; Dawson-type; Keggin-type; Vanadium (V)-substituted; Titanium (IV)-substituted; Catalysis; Toluene oxidation; Supported-organometallic complex; 修飾へテロポリ酸塩; タングストポリ酸塩; Cp^*RH^<2+> 基; ベンゼン酸化; 触媒前駆体; 金属置換; ニオブ(V); チタン(

Several novel results in this research were obtained :1. The Cp^*Rh^<2+> complex (Cp^* = C_5Me_5) supported on the V_3 surface (B-site) of 1, 4, 9-tri-vanadium(V)-substituted Keggin polyoxotungstate [1, 4, 9-PW_9V_3O_<40>]^<6-> was synthesized. The product also contained [Cp^*Rh(DMSO)_3]^<2+> as counterion.2.Tri-Ti^<IV>-and di-Ti^<IV>-substituted Keggin polyoxotungstate were isolated as potassium salts and their X-ray crystal structures determined. Ultracentrifugation molecular weight (MW) measurements were also performed in aqueous solution. The two Ti^<IV>-substituted compounds in the solid state were dimeric, Ti-O-Ti anhydride forms of two α-Keggin [1, 2, 3-PW_9Ti_3O_<40>]^<9-> units and of two novel α-Keggin [1, 2-PW_<10>Ti_2O_<40>]^<7-> units, respectively. Solution MW measurements showed that the former was a dimer in pH7.0 aqueous solution, whereas the latter was a monomer in pH 7.8 aqueous solution.3. The supported-polyoxotungstates formed between tri-metal-substituted Dawson polyoxotungstate [P_2W_<15>M_3O_<62>]^<9-> (M = Nb^V, V^V) and organometallic groups ((cod)Pt^<2+> and Cp^*Rh^<2+>) were synthesized, and the effects polyoxoanion-support (Nb vs. V) and organometallic species ((cod)Pt^<2+> vs. Cp^*Rh^<2+>) were elucidated.4. Oxidation products of toluene and nitrobenzene with 30% aqueous H_2O_2 catalyzed by several vanadium(V)-substituted Keggin and Dawson polyoxometalates were carefully analyzed by GC/MS measurements. Polyoxometalates which promote the reaction via an ionic mechanism and via a radical mechanism were classified.

本研究获得了以下新的结果：1.合成了负载在1，4，9-三钒（V）取代的Keggin多钨酸盐[1，4，9-PW_9V_3O_ ]_x的V_3表面（B位）上的Cp^*Rh^&lt;2+&gt;配合物（Cp^* = C_5Me_5）<40><6->。2.分离得到了三Ti ^<IV>-和二Ti ^<IV>-取代的Keggin多钨酸盐钾盐，并测定了它们的X-射线晶体结构。还在水溶液中进行超离心分子量（MW）测量。这两个钛取代<IV>化合物在固态下分别是两个α-Keggin [1，2，3-PW_9Ti_3O_<40>]^<9->单元和两个新的α-Keggin [1，2-<10>PW_Ti_2O_<40>]^<7->单元的二聚体、Ti-O-Ti酸酐形式。溶液MW测量表明，前者在pH 7.0水溶液中为二聚体，而后者在pH 7.8水溶液中为单体。3.合成了三金属取代的Dawson多钨酸盐[<15>P_2W_M_3O_<62>]^<9->（M = Nb^V，V^V）与金属有机基团（（cod）Pt^2+和Cp^*Rh^2+）形成的配合物，并研究了多阴离子载体（Nb vs. V）和金属有机物种（（cod）Pt^2+ vs. Cp^*Rh^2+）对配合物的影响.用GC/MS法对几种钒（V）取代的Keggin和Dawson杂多酸盐催化甲苯和硝基苯在30%H_2O_2水溶液中的氧化产物进行了分析。对通过离子机理和通过自由基机理促进反应的聚氧乙烯酸酯进行了分类。

项目成果

K.Nomiya et al.: "Active sites of vanadium-substituted POM catalysts on benzene hydroxylation"J.Mol.Catal.. A152. 55-68 (2000)

K.Nomiya 等人：“钒取代 POM 催化剂对苯羟基化的活性位点”J.Mol.Catal.. A152。

K.Nomiya et al: "Benzene hydroxylation with hydrogen peroxide catalyzed by vanadium(V)-substituted POMs"J.Mol.Catal.,2000. (in press).

K.Nomiya 等人：“钒 (V) 取代的 POM 催化的过氧化氢苯羟基化”J.Mol.Catal.，2000。

K.Nomiya et al.: "Benzene hydroxylation catalyzed by vanadium(V)-substituted POMs"J.Mol.Catal.. A156. 143-152 (2000)

K.Nomiya 等人：“钒 (V) 取代的 POM 催化的苯羟基化”J.Mol.Catal.. A156。

K.Nomiya et al.: "Multicenter active sites of vanadium-substituted polyoxometalate catalysts on benzene hydroxylation with hydrogen peroxide and two reaction types with and without an induction period"J.Mol.Catal.. Vol.A152. 55-68 (2000)

K.Nomiya 等人：“钒取代的多金属氧酸盐催化剂对过氧化氢苯羟基化的多中心活性位点以及有和没有诱导期的两种反应类型”J.Mol.Catal.. Vol.A152。

K.Nomiya et al.: "Synthesis of Triniobium(V)-Substituted SiW_9Nb_3O_<40>^<7-> Heteropolyoxoanions"Bull.Chem.Soc.Jpn.. 71(11). 2603-2610 (1998)

K.Nomiya等人：“Trniobium(V)-取代的SiW_9Nb_3O_<40>^<7->杂多氧阴离子的合成”Bull.Chem.Soc.Jpn..71(11)。