185 resultados para Metal complexes


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Iron phenanthroline - and 8 - hydroxyquinoline complexes /Y zeolite, denoted a FePhen/Y and FeOx/Y respectively, were prepared; The formation of the metal complexes mentioned above within the cages of Y zeolite and their crystal structures were determined by elemental analyses, diffuse reflectance UV-Vis,SEM,BET,and XRD methods; The influence of experimental parameters upon phenol conversion and product selectivities were investigated as well.

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Cobalt(II) phenanthroline and 8-hydroxyquinoline complexes/Y zeolite, denoted as CoPhen/Y and CoOx/Y respectively, were prepared, The formation of the metal complexes mentioned above within the cages of Y zeolite and their crystal structures were determined by elementary analyses, TG-DTA, diffuse reflectance UV-Vis, SEM, BET and XRD methods. The influence of experimental parameters upon phenol conversion and product selectivities was investigated as well.

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The hydrogenation of alkali metals using lanthanide trichloride and naphthalene as catalyst has been studied. LnCl3(Ln = La, Nd, Sm, Dy, Yb) and naphthalene can catalyze the hydrogenation of sodium under atmospheric pressure and 40-degrees-C to form sodium hydride. The activities of lanthanide trichlorides are in the following order: LaCl3 > NdCl3 > SmCl3 > DyCl3 > YbCl3. Although lithium proceeds in the same catalytic reaction, the kinetic curve of the lithium hydrogenation is different from that of sodium. Lanthanide trichlorides display no catalytic effect on the hydrogenation of potassium in presence of naphthalene. The mechanism of this reaction has been studied and it is suggested that the anion-radical of alkali metal naphthalene complexes may be the intermediate for the hydrogenation of alkali metals and the function of LnCl3 is to catalyze the hydrogenation of the intermediate. The products are porous solids with high specific surface area (83 m2/g for NaH) and pyrophoric in air. They are far more active than the commercial alkali metal hydrides. The combination of these hydrides with some transition metal complexes exhibits high catalytic activity for the hydrogenation of olefins.

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Thiazolyl heterocyclic azo dye and its metal (Ni2+, Co2+)-azo complexes were synthesized. Their structures were confirmed by elemental analysis, UV-VIS absorption spectra, FT-IR, H-1 NMR and MALDI-MS. The thermal properties of metal complexes were studied by DSC-TGA. The optical constants (complex refractive index N=n + ik) and thickness of the complex thin films on polished single-crystal silicon substrates were investigated on a scanning ellipsometer. Results indicate that thiazolyl metal-azo complexes possess good optical and thermal properties. They would be a promising recording medium candidate for NVD with the Super-resolution near field structure (Super-RENS) technology. (c) 2007 Elsevier B.V. All rights reserved.

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合成了2-(2-氨基-6-乙氧基苯并噻唑基偶氮)-5-(N,N-二乙基氨基)三氟甲基磺酰苯胺偶氮染料(EBTDATFS)及其与乙酸镍、乙酸钴、乙酸铜、乙酸锌等金属盐鏊合的金属鏊合物。通过红外光谱、紫外-可见吸收光谱和MALDI质谱等对染料及其金属鏊合物进行了结构表征;使用旋涂方法在K9玻璃和抛光的单晶硅基片上制备薄膜;研究了镍金属鏊合物的热学性能;使用椭偏仪研究了Ni和Zn鏊合物的光学常数。结果表明:4种金属鏊合物薄膜最大吸收光谱为621-629nm,且长波边吸收峰陡峭;TGA-DSC测试结果表明镍金属鏊

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采用溶液析出法,合成了以2-(2′-羟基-5′-甲基苯基)苯并三唑(HMPB)为配体的多氮杂环金属配合物M(HMPB)2(M=Co,Ni),利用元素分析、激光解析飞行时间质谱等进行了表征,并研究了新配合物的红外特征光谱和紫外-可见电子吸收光谱。结果表明:HMPB配体通过N和O原子与中心金属以二齿形式配位,中心金属的配位数为4;配合物红外特征吸收谱带位于400~2 500 cm^-1,形成金属配合物后,2-(2′-羟基-5′-甲基苯基)苯并三唑的羟基的伸缩振动吸收、CN振动峰和C─O特征吸收有明显改变,同时确定了配位键M─N和M─O的特征峰位置;配合物在紫外区有强吸收,其最大吸收峰位于335~345 nm。

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本论文共合成了两种类型12个稀土金属配合物和一个硅化合物,分别对它们进行了红外、核磁等表征,对其中的9个配合物进行了晶体结构的测定。考察了配体结构和反应条件对所生成的配合物结构的影响,研究了稀土单烷基配合物的反应性,以及稀土双烷基配合物在烷基铝和有机硼盐的共同作用下对丁二烯聚合的催化活性和选择性。主要工作内容和结论如下: (1) 合成了噻吩苯胺配体(HL1),该配体与(Lu,Y)稀土三烷基化合物反应,通过C–H活化和烷基消除反应制备了稀土(Lu,Y)单烷基配合物1和2,配体以少见的C,N模式配位,S原子并不参与配位。配体(HL1)与Sc三烷基化合物反应制备了配体分别以C, N和N, S配位的双配的Sc配合物5。 (2) 通过改变反应时间和溶剂体系,HL1与稀土钇三烷基化合物反应可得到罕见的由稀土烷基化物和胺化物两部分组成的配合物3,它们通过噻吩环上活化的C原子连接在一起。HL1和Lu(CH2SiMe3)2(THF)2LiCH2SiMe3在甲苯和正己烷溶剂中反应可得到以L12Lu(CH2SiMe3)2为阴离子,Li(THF)4为阳离子的离子对4。 (3) 研究配合物1和2的反应性。1和2与过量的PhSiH3反应得到中心金属与Si元素交换的Si化合物。 (4) 合成了噻吩苯基膦胺配体(HL2-4)和苯基膦胺配体(HL5)配体。HL2-5与稀土(Y, Lu和Sc)三烷基化合物反应制备了稀土双烷基配合物6,7,8,9,10,11和12。进一步研究了稀土金属双烷基配合物6–12对丁二烯的催化特性,发现该系列催化剂具有独特的催化性质,能够催化丁二烯高反1,4-聚合(91.3%),得到的聚合物分子量在1到2万之间,分子量分布较窄(1.4–1.6)。 (5) 研究了金属钇(Y),镥(Lu),钪(Sc)三种中心金属对丁二烯聚合活性和反式1,4选择性的影响,发现催化剂对丁二烯聚合活性和反1,4选择性取决于配合物的中心金属原子,其中选择性最高为钪配合物,催化活性最佳的为钇配合物。 (6) 研究了配体HL2-4的N-芳环上的取代基分别为甲基,乙基,异丙基时催化体系对丁二烯反式1,4聚合活性和选择性的影响,发现随着N-芳环上取代基空间位阻的增大,催化剂活性逐渐下降,选择性逐渐增加,但当其取代基为异丙基时,过大的空间位阻导致活性和选择性同时有明显的下降。我们通过改变噻吩基为苯基,比较了相同聚合条件下含噻吩基的稀土双烷基配合物和含苯基的稀土双烷基配合物对丁二烯聚合活性和选择性的影响,发现噻吩环的存在对催化剂的活性和选择性有较大的影响。 (7) 在相同催化剂条件下,研究了不同聚合条件(不同类型的AlR3,不同类型的Borate,Al/Ln比等)对丁二烯反1,4聚合活性和选择性的影响。 我们发现,在AlR3和Borate这两种影响因素中,以烷基铝的类型对催化剂催化活性和选择性的影响最大,而有机硼盐的影响则比较轻微,其中以烷基铝为AliBu3,Borate为[B(C6F5)4][Me2NHPh]时,反1,4选择性为最佳。Al/Ln增大并不能够显著增加催化剂的活性,对选择性的影响也并不明显,相反,随着铝比的增加,聚合过程中的链转移增加,导致分子量下降,对于该系列稀土烷基催化剂,最佳Ln/Al 为10。

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本文以调控发光颜色、提高发光效率为目的,通过改变配体、中心金属离子、取代基等进行颜色调节;通过引入电子或空穴传输单元,实现发光分子的功能化进而改善载流子传输提高发光效率。文中主要以有机小分子和金属配合物为研究对象,它们本身都具有良好的发光性质。工作集中围绕以下几个问题展开:1、PPV齐聚物是一类高效发光的分子体系,如果在其中嵌入8一取代的哇琳单元对发光会有什么影响?2、使用含噁二唑(具有电子传输功能)的配体得到的金属配合物是否能同时拥有双重功能,即高效发光(金属配合物的特点)和优良的电子传输?3、由N2O-双齿配体转变成N,N-双齿配体,配合物的发光又会如何?4、稀土配合物具有高的光致发光效率,但电致发光效率非常低,能否通过咔哇或呛二吟功能化来改善载流子传输,提高电致发光效率?主要工作及取得的结果概述如下:1、经由Knoevenagel缩合反应合成了一系列共骊的2,21-(1,4-芳二乙烯基)双-8-取代喹啉。单晶X-射线衍射研究表明固态下存在分子间,π…π堆积相互作用,这对于载流子传输是比较有利的。喹啉8-位于的取代基的变化对发光影响不大,表明刚性共扼骨架对发光起主要贡献。改变中心的芳核,明显可以调控发光颜色。当存在分子内电荷转移时,与不存在的相比,发光显著红移。电致发光性质表明这些含双喳琳的PPV齐聚物是良好的发光和电子传输材料。2、存在分子内氢键的化合物2-(2-羟基苯基)-5-苯基-1,3,4-噁二唑(HOXD),具有激发态分子内质子转移(ESIPT)特性。在室温下,用365脚的紫外灯照射时表现强的兰色荧光。室温和低温(77K)下的磷光光谱表明它在固态下具有较强的磷光发射,与理论预测完全一致。多层电致发光器件ITO加PB/HOXD/BCP/Alq3/Mg:Ag最大亮度达到656cd/m2,电流效率为0.37cd/A。当把HoxD掺在cBP中时,亮度和效率都有一定程度的提高,达到870cd/m2和0.82cd/A。3、合成了含有德二哩配体(HOXD)的碱金属配合物MOxD(M=Li,Na,K)。我们发现配合物的发光颜色取决于中心金属离子,LiOXD是一个优良的蓝光材料,半峰宽是65nm,发射峰位在478nm,它也可以作为界面材料使用,起到和LIF相同的作用,即改善电子注入。同时作者首次报道了钠和钾的配合物可以用作发光材料。电致发光性质表明这些配合物是优良的蓝/绿色发光和电子注入/传输材料。4、使用从N双齿配体代替N,O-双齿配体(比如8-羟基喹啉),合成了含有2-(2-羟基喹啉)苯并咪唑的锌、铍和硼配合物。用硼配合物作为发光层的三层器件ITO/NPB/boron-complex/Alq3/LiF/A1所得到的光谱覆盖了从400到750nm的区域,表明获得了一个很好的白色发光。白光分别源于激子和激基复合物发光,由三种成分构成:来自于硼配合物的兰色发光(490nm);来自于Alq3的发光(535nln);NPB和BPh2(Pybm)界面形成的激基复合物发光(610nm)。器件最大亮度是110cd/m2最大效率是0.8cd/A。5、设计、合成了咔唑、噁二唑功能化的稀土馆配合物,期望通过改善空穴和电子传输来提高发光效率。含咔哇的配合物的双层器件发光光谱较宽,包括三价铺的特征发射和一个宽峰,可能是咔唑的发光。当使用TPD做空穴传输层时,噁二唑铺配合物的电致发光器件得到纯正明亮的红色发光,器件结构为ITO/TPD(40nm)/(OXD-PyBM)Eu(DBM)3(SOnm)/LiF(Inm)/Al(200m),启动电压为7.8V,在21v时达到最大亮度322cd/m2。亮度为57cd/m2和13.sv时电流效率最大,为1.9cd/A,对应外量子效率是1.7%。高的效率表明通过引入噁二唑基团,配合物的电子传输能力得到明显改善。6、初步研究了三线态发光的铱的金属有机配合物,得到了高亮度、高效率的绿色发光;对8-羟基喹啉锌配合物的高分子化也做了初步探讨。

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Five, novel, meso-tetra[4-(3,4,5-trialkoxybenzoate)phenyl]porphyrins and their metal complexes were synthesized and their molecular structures were confirmed by H-1 NMR, FTIR spectroscopy and elemental analysis. Mesomorphic studies using DSC, polarizing optical microscope and X-ray diffraction revealed that all compounds exhibited thermotropic columnar mesophases over a wide mesophase temperature range and low liquid crystalline-crystal line transition temperature. (c) 2007 Elsevier Ltd. All rights reserved

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Novel channel structures based on [M(bpdo)(3)](2+) and p-sulfonatocalix[4]arene nanocapsules have been established; these are sustained exclusively by charge-assisted pi...pi interactions and sorption experiments show the porous materials have selective guest sorption properties.

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The B3LYP hybrid density functional method has been carried Out to Study theoretically the mechanisin of Pd(0)-catalyzed alkyne cyanoboration reaction. Both the intermolecular and intramolecular alkyne cyanoboration reactions were studied. For each reaction, three paths were proposed. In path A of each reaction, the first step is B-CN bond oxidative addition to bisphosphine complex Pd(PH3)(2), in path B of each reaction, the first step is alkyne coordination to bisphosphine complex Pd(PH3)2, and in path C of each reaction, the first step is the PH3 dissociation front Pd(PH3)2 to form monophosphine complex Pd(PH3) For both reactions, path B is favored.

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The reaction mechanism of the Pd(0)-catalyzed alkyne cyanothiolation reaction is investigated by MP2, CCSD(T) and the density functional method B3LYP. The overall reaction mechanism is examined. The B3LYP results are consistent with the results of CCSD(T) and MP2 methods for the isomerization, acetylene insertion and reductive elimination steps, but not for the oxidative addition step. For the oxidative addition, the bisphosphine and monophosphine pathways are competitive in B3LYP, while the bisphosphine one is preferred for CCSD(T) and MP2 methods.

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Efficient white organic light-emitting diodes (WOLEDs) using europium complex as the red unit are presented. The WOLEDs were fabricated by using the structure of indium tin oxide (ITO)/N, N'-di(naphthalene-1-yl)-N, N'-diphenyl-benzidine (NPB)/4,4-N, N-dicarbazolebiphenyl (CBP) : bis(2,4-diphenylquinolyl-N, C-2) iridium (acetylacetonate) ((PPQ)(2)Ir(acac)) : Eu (III) tris(thenoyltrifluoroacetone) 3,4,7,8-tetramethyl-1,10-phenanthroline (Eu(TTA)(3)(Tmphen))/NPB/2-methyl-9,10-di(2-naphthyl)anthracene (MADN) : p-bis (p-N, N-di-phenyl-aminostyryl)benzene (DSA-Ph)/9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP)/tris(8-hydroxyquinoline) aluminium (Alq3)/LiF/Al.