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1.
LI Jie  HUANG Yuan  HAN Qiu-Xia 《结构化学》2013,(12):1897-1903
A new decatungstate incorporated metal-organic framework {[Co2(bpdo)5(H2O)n- W10O32]}n·nbpdo·2nH2O(1, bpdo = 4,4'-bis(pyridine-N-oxide) has been synthesized through a one-step hydrothermal reaction and characterized by elemental analyses, IR, solid UV-vis absorption spectra, and single-crystal X-ray diffraction. The structural analysis indicates that 1 displays a one-dimensional ladder structure with [W10O32]4- as guest incorporated by electrostatic interaction. The photocatalytic property of the framework toward a rhodamine B (RhB) solution was also investigated. The results indicated that compound 1 possesses high photocatalytic activity in heterogeneous system under sunlight irradiated.  相似文献   
2.
合成新型N-甲基吗啉十聚钨酸盐[Mor1,2]4W10O32,对其进行提纯、表征和催化性能研究。催化体系是以[Mor1,2]4W10O32为催化剂,30%H2O2为氧化剂,催化氧化环己醇制备环己酮。考察催化剂用量、氧化剂用量、反应温度变化和反应时间变化对环己酮产率的影响,确定最佳反应条件为:反应温度80℃、环己醇用量5mmol、催化剂用量30μmol、氧化剂H2O2用量12.5 mmol,反应时间6小时,此时环己酮产率可达到96%。  相似文献   
3.
The use of decatungstate in combination with silanes to generate silyl radicals under green fluorescence bulb irradiation as well as sunlight exposure is described. The mechanisms are investigated by ESR and laser flash photolysis experiments. The high potential of this reaction is evidenced here when using a decatungstate/silane/diphenyl iodonium salt combination as an initiating system for the ring opening photopolymerization of epoxides.

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4.
A mild and selective C(sp3)?H aerobic oxidation enabled by decatungstate photocatalysis has been developed. The reaction can be significantly improved in a microflow reactor enabling the safe use of oxygen and enhanced irradiation of the reaction mixture. Our method allows for the oxidation of both activated and unactivated C?H bonds (30 examples). The ability to selectively oxidize natural scaffolds, such as (?)‐ambroxide, pregnenolone acetate, (+)‐sclareolide, and artemisinin, exemplifies the utility of this new method.  相似文献   
5.
 The design of new heterogeneous photooxygenation systems able to employ visible light, oxygen, mild temperatures, and solvent with a low environmental impact has been investigated. In particular, the heterogenization of decatungstate (W10O4-32), a polyoxometalate with photocatalytic activity in oxidation reactions, has been carried out in polymeric membranes of polyvinylidenefluoride. The polymeric catalytic membranes prepared by phase inversion technique have been successfully applied in the aerobic mineralization of phenol in water, which was used as an example of organic pollutant. In order to evaluate the effect of the polymeric environment on the overall catalyst behavior, we have also heterogenized the decatungstate (opportunely functionalized) in perfluorinated membrane made of Hyflon. The photocatalytic composite membranes are characterized by different and tuneable properties depending on the nature of the polymeric micro-environment, in which the catalyst is confined. Moreover, the selective separation function of the membrane results in enhanced performance in comparison with homogeneous reactions.  相似文献   
6.
反应控制相转移催化剂催化环己烯氧化制己二酸   总被引:5,自引:0,他引:5  
郭明林 《催化学报》2003,24(7):483-484
The goal of modern organic synthesis is to develop efficient catalytic methods to produce desired compounds in a cost-effective and environmentally benign manner. Hydrogen peroxide is a highly attractive oxidant because it is a cheap, mild and environmentally friendly reagent with a high content of active oxygen, and water is the only by-product.  相似文献   
7.
Si,Ti,Ta,Nb,Zr,V,Pt,W,Mo等元,因在物质分离、催化、导电材料上有着极大的应用前景,而引起了人们的高度重视[1-6].两亲性表面活性剂已被证明由于聚集生成胶束而起模板作用,构筑生成多孔材料[7,8].[9].由于二胺无法聚集生成胶束,因此具有与单胺不同的模板机制.Pinnavaia报导[10].而质子化了的二胺阳离子,其模板作用未见报导.本文报导酸性条件下以质子化了的癸二胺为模板合成十聚钨酸多孔材料的研究,同时对其模板作用进行了探讨.1实验部分(1)样品制备将0.001mol癸150mL去离子水中,用浓盐酸调pH值为1.待二胺完全溶解后,将75mL含有等摩…  相似文献   
8.
有机铵十聚钨酸盐在溶液中的光致变色性质研究   总被引:7,自引:0,他引:7  
有机铵十聚钨酸盐具有显著的光致变色性质,电子自旋共振研究表明光致变色是由于光照过程中有五价钨生成,发生了光还原反应。本文研究了二异丙胺和六氢吡啶十钨酸盐(分别简写为DIAW_(10)和PIPDW_(10)在溶液中的光致变色性质,考察了水、乙腈、二甲基甲酰胺(DMF)、二甲基亚砜(DMSO)对光致变色性质的影响,对比研究了四丁基铵盐(NBuW_(10))的情况,还测定了不同光照时间下W(V)浓度,可见吸收光谱和循环伏安,提出了光致变色性质与体系中所含活泼氢的定量关系,初步揭示有机铵十聚钨酸盐光致变色的本质。  相似文献   
9.
以粉状白钨酸为原料,利用它的离子交换性能制得了碱金属及铵的酸式十聚钨酸盐M_3HW_(10)O_(32)·11H_20(M=NH_4、Li、Na、K)。测定了它们的差热分析、X-射线粉末衍射、IR和UV光谱,在水溶液中的稳定性以及光致变色等性质。  相似文献   
10.
研究了某些DMF和DMSO配位的金属十聚钨酸盐在 3 种有机溶剂中的光致变色性质,通过ESR、NMR和可见吸收光谱的研究及对五价钨的测定,说明了光致变色性质的产生与金属阳离子无关,而取决于十聚钨酸根W10O324-、金属离子的配体及所采用溶剂。  相似文献   
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