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1.
铁取代钨硅酸盐位置异构体的合成、表征及电化学性质   总被引:5,自引:0,他引:5  
取代型杂多酸盐( HPC)具有金属卟啉的类似结构 ,它可以代替金属卟啉在很多反应中作催化剂 [1],被称为无机金属卟啉。 Hill[2],Neumann[3]分别报道了过渡元素单取代的杂多阴离子 [PW11M(H2O)O39]n-, [SiW11Ru(H2O)O39]n-对烯烃环氧化反应具有催化活性。目前,在单取代的杂多配合物中,β异构体的报道很少,我们发现,某些单取代金属衍生物中,β异构体具有良好的催化活性,具有明显的应用前景。继过去的工作 [4],我们又研究了过渡元素取代的 11-系列杂多阴离子的某些性质。有关α-XW11Fe(H2O)O39n-( X=Si, P, Ge, As…  相似文献   

2.
十一钨钛硅酸盐的合成,表征及电化学性质   总被引:1,自引:0,他引:1  
合成了钛取代杂多硅钨酸盐K6SiW11TiO40·16H2O(SiW11Ti),并用元素分析、红外光谱、紫外-可见光谱和183WNMR谱进行表征.对其溶液电化学性质进行了讨论.其还原过程包括钛的单电子还原和钨的双电子两质子加合过程.在弱酸性溶液中SiW11Ti对NO-2的还原有良好的催化作用  相似文献   

3.
十一钨锰硅酸盐异构体的电化学性质及其催化性能   总被引:4,自引:0,他引:4  
报道了十一钨锰硅酸盐异构体α-,β  相似文献   

4.
合成了通式为K_(13)[Ln(β_i-SiW_(11)O_(39))_2]·xH_2O(Ln=La,Ce,Pr,Nd,Sm,Gd,Er;β_i=β_1,β_3)的两个系列的β-异构体。通过元素分析、极谱、循环伏安法,UV和VIS光谱、磁化率以及热分析等手段研究了异构体的组成和性质。  相似文献   

5.
环氧化反应催化活性;十一钨锰硅酸盐异构体的电化学性质及其催化性能  相似文献   

6.
合成了通式为K5-nHn[α-,βi-SiW11M(H2O)O39]·xH2O(M=Al,Ga,βi=β1,β2,β3)的八种异构体。通过元素分析、红外光谱和紫外光谱、极谱和循环伏安、27Al和183W核磁共振、X光电子能谱等方法进行了表征。所合成的各异构体在催化以H2O2为氧化剂的顺丁烯二酸环氧化反应中,β3异构体具有最高的催化活性  相似文献   

7.
十一钨锌杂多配合物位置异构体的合成、表征及催化性能   总被引:6,自引:0,他引:6  
Keggin结构阴离子 SiW12O404-主要有α和β两种异构体。 SiW12O404-由一个中心原子 Si和四个 W3O13集团构成。当四个 W3O13共角相连,并以四面体方式配位于 Si周围就构成了α 异构体( Td对称性),α异构体中的一组 W3O13基团绕 C3轴旋转 60°,则构成了β 异构体( C3V对称性)。在β SiW12O404-结构中存在 3种不同环境的钨原子,当失去一个 WO4+后,可衍生出 3种含有缺位的β i SiW11O398-异构体。若空位位于旋转组的对位,称为β 1 SiW11O398-型体,若空位位于旋转组的相邻的钨原子位置,称为β 2 SiW…  相似文献   

8.
过渡元素取代的杂多配合物由于其独特的催化活性和抗病毒性受到人们的重视 ,由于缺位 β位的介稳定性和异构化 ,给合成带来了一定的困难。我们发现 ,某些单取代金属衍生物中 β异构体具有良好的催化活性[1 ,2 ] 。本文报道了通式为α ,βi K6[SiW1 1 ZrO40 ]·XH2 O( βi=β1 ,β2 ,β3)的四种异构体 (简记作α ,β SiW1 1 Zr)的合成、表征及四种异构体对烯烃环氧化反应的催化活性 ,为研究Zr杂多化合物的应用提供选择。1 实验部分1 1 仪器与试剂日本岛津IR 40 8红外光谱仪 (KBr压片 ) ,美国PE公司产λ 35型紫外分光光谱仪 ;384B…  相似文献   

9.
钛取代的钨硅杂多配合物位置异构体的合成、表征及催化性能;钨钛杂多化合物;催化活性;环氧化反应  相似文献   

10.
β—九—钨镓杂多配合物异构体的合成方法及性质研究   总被引:2,自引:0,他引:2  
本文报道了β-九-钨镓杂多阴离子的合成方法——配位平衡竞争法,首次合成了5种通式为(?)[β-GaW_9O_(34)H]·xH_2O(M=Na~+,K~+,NH_4~+,MeN~+,Et_4N~+)的盐,并以β-(GaW_9O_(34)H]~(10-)为母体,合成了M_8H_3[β-GaW_9Mn_3(H_2O)_3O_(37)]·xH_2O(M=Na~+,K~+)盐,通过IR、UV、极谱和CV、ESR、μ_(err)和DTA等方法对化合物进行了表征,证明标题化合物为三缺位、有配位反应活性和Keggin结构骨架的杂多化合物异构体.  相似文献   

11.
The novel substituted 2,3-dichloro-1,4-naphthoquinone derivatives were synthesized from the reactions of (1) and related nucleophilles in sodium carbonate (Na2CO3) solution of ethanol, chloroform with Et3N, or potassium carbonate (K2CO3) solution of acetonitrile. The structures of novel compounds were characterized by using microanalysis, Fourier transform–infrared, 1H NMR, 13C NMR, mass spectrometry, and cyclic voltammetry (CV).

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]  相似文献   


12.
Ferrocenyl‐substituted silanes via the reaction between mono and dilithio‐ferrocene with trimethyl, trietheyl, vinyldimethyl or t‐butyldimethyl chlorosilanes is prepared. The electrochemical behaviors of these compounds were investigated by cyclic voltammetry. This work describes the electrochemical and electrocatalytic properties of carbon ceramic electrode (CCE) modified with ferrocene composites as a new electrocatalyst material.  相似文献   

13.
王军  董海山  黄奕刚  周小清  李金山 《合成化学》2006,14(2):131-134,138
将含能化合物3-氨基-4-氯肟基呋咱(ACOF)在低温下用稀碱处理后发生过渡中间体3-氨基-4-氰基呋咱氧化物(ACFO)的二聚关环反应合成了新型呋咱类含能化合物3,4-二氨基呋咱基氧化呋咱异构体(DAFF iso-m er),产率达66.3%。培养了DAFF isom er的单晶。用四圆单晶X-射线衍射仪,1H NMR,13C NMR,IR,MS及元素分析对其结构进行了表征。结果表明:DAFF isom er晶体属三斜晶系,空间群P-1,分子呈平面构型,层状晶体内存在分子内和分子间氢键,晶胞堆积层间不存在氢键。  相似文献   

14.
In this study novel peripherally tetra 1,3-diethoxy-2-propanol substituted Co(II), Cu(II), Mg(II), Ni(II) Zn(II) phthalocyanine derivatives were prepared. The characterization of the novel compounds was made by FT-IR, 1H-NMR, UV-vis and MALDI-TOF mass. Electrochemical, in-situ spectroelectrochemical and electrocolorimetric measurements have been carried out with the aim to determine the redox properties, to illuminate reaction mechanism and the effect of substituent and metal center. Moreover, the color properties and aggregation tendency of compounds were also investigated.  相似文献   

15.
This study establishes structure–property relationships for four synthetic flavin molecules as bioinspired redox mediators in electro‐ and photocatalysis applications. The studied flavin compounds were disubstituted with polar substituents at the N1 and N3 positions (alloxazine) or at the N3 and N10 positions (isoalloxazines). The electrochemical behavior of one such synthetic flavin analogue was examined in detail in aqueous solutions of varying pH in the range from 1 to 10. Cyclic voltammetry, used in conjunction with hydrodynamic (rotating disk electrode) voltammetry, showed quasi‐reversible behavior consistent with freely diffusing molecules and an overall global 2e?, 2H+ proton‐coupled electron transfer scheme. UV/Vis spectroelectrochemical data was also employed to study the pH‐dependent electrochemical behavior of this derivative. Substituent effects on the redox behavior were compared and contrasted for all the four compounds, and visualized within a scatter plot framework to afford comparison with prior knowledge on mostly natural flavins in aqueous media. Finally, a preliminary assessment of one of the synthetic flavins was performed of its electrocatalytic activity toward dioxygen reduction as a prelude to further (quantitative) studies of both freely diffusing and tethered molecules on various electrode surfaces.  相似文献   

16.
The p-NiO/n-TiO2/polyaniline composites were synthesized via in situ polymerization of aniline. The structure and morphology of the composites were characterized by means of X-ray diffraction(XRD), scanning electron microscopy(SEM), Fourier transform infrared spectroscopy(FTIR) and UV-Vis absorption spectroscopy. It was found that the p-n junction p-NiO/n-TiO2 particles were trapped in the polyaniline molecular matrix and the polyaniline was deposited on the surface of the particles to form a kind of flower cluster morphologies. The electrochemical behavior of the polyaniline composites was investigated. The electrochemical reactivity of the polyaniline was influenced by the p-NiO/n-TiO2 particles due to the effect of electron-hole pairs in these p-n junction particles. The reversibility of redox process and current intensity of the polyaniline composites with the changing of potential scan rate were also discussed.  相似文献   

17.
乙炔二茂铁的合成表征和电化学性质测定   总被引:1,自引:0,他引:1  
选择了一条反应条件温和且比较经济的反应途径,在惰性气氛中合成了一系列二茂铁衍生物的重要合成中间体——乙炔二茂铁。通过UV、IR、^1H NMR对化合物进行了表征,运用CV测定了电化学性质。该实验作为综合化学实验,有助于学生了解化学研究的一般过程,掌握惰性气氛合成技术及柱色谱分离方法,提高学生综合分析问题和解决问题的能力。  相似文献   

18.
合成了一种草酰胺桥联大环二羰四胺Ni(Ⅱ )单核配合物 ,并以此为母体合成了Ni (Ⅱ ) -Cu (Ⅱ )双核配合物 .用元素分析、红外光谱、差热分析、紫外光谱、摩尔电导以及循环伏安等测试手段对配合物进行了表征和电化学性质研究 .经分析 ,标题配合物具有草酰胺桥联结构 ,Ni(Ⅱ )处于平面正方场 ,Cu (Ⅱ )处于八面体场中 .循环伏安测试表明此类配合物能稳定Ni(Ⅲ ) .  相似文献   

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