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1.
铜(Ⅰ,Ⅱ)配合物的合成、结构与性质   总被引:4,自引:0,他引:4  
在室温、有关配体存在下,利用金属铜粉和过氧化苯甲酰的氧化加成配位反应合成了四种铜(Ⅱ)配合物(配体分别为联吡啶、双二苯基膦乙烷、2-氨基吡啶、苯并咪唑)。同时又利用双齿有机膦配体(dppm=双二苯基膦甲烷,dppe=双二苯基膦乙烷,dppp=双二苯基膦丙烷,dppb=双二苯基膦丁烷)和金属铜盐的还原取代反应合成了四种一价铜(Ⅱ)配合物。通过元素分析确定了配合物的组成,经X射线四圆单晶衍射确定了配合物的分子结构,配合物的晶体结构由直接法和Fourier合成方法解出。利用电子光谱等手段研究了氧化加成配位和还原取代配位反应的机理。初步建立了一套简单有效的合成铜(Ⅰ,Ⅱ)配合物的新方法。  相似文献   

2.
苯并咪唑杂环具有良好的配位选择性,能与多种金属形成配合物.这些配合物往往具有优良的生理、荧光、催化等性能.综述了近年来含有苯并咪唑衍生物的过渡金属配合物的合成方法及其在催化乙烯齐聚和聚合方面的研究进展,并讨论了配合物的结构因素如取代基的电子效应、位阻效应等对配合物催化性能的影响规律.  相似文献   

3.
以水杨醛为母体, 与胺类化合物缩合形成席夫碱配体, 用分子自组装法合成了一系列水溶性席夫碱型金属锰单核、双核配合物. 通过元素分析、红外光谱对配合物进行了表征, 采用邻苯三酚自氧化法测定了配合物的超氧化物歧化酶(SOD)活性. 结果表明, 这些水溶性锰配合物具有良好的SOD活性.  相似文献   

4.
非平面分子内电荷转移离子配合物的合成及其光物理性质   总被引:4,自引:0,他引:4  
N-乙烯基咔唑三羰基铬为模板化合物, 选用丙烯基阳离子取代其中一个羰基配体, 合成了一种新型非平面分子内电荷转移有机金属配合物. 通过元素分析、红外、核磁共振确定了配合物的组成和结构, 电子吸收和荧光光谱结果表明配合物的光物理行为可通过配体取代调控.运用双光束前向简并四波混频(DFWM)的方法, 测试了配合物及配体的三阶非线性效应, 同时探讨了金属配位和配体取代对其的影响.  相似文献   

5.
汪阳  阎敬灵 《化学学报》2023,(3):275-288
催化剂在推动聚烯烃工业发展中有着举足轻重的作用,其中金属催化剂的设计与合成更是金属有机催化化学的关键.稀土金属具有独特的轨道结构、反应活性和配位准则,因此稀土金属配合物通过在金属中心周围引入空间位阻,在聚烯烃材料制备中表现出独特优势.其中配体是决定稀土金属配合物的结构、化学活性及稳定性等方面的关键因素.本综述介绍了茂基配体(烷基取代、芳基取代、茚和芴配体)和非茂基配体(大环四齿配体、三齿配体、双齿配体和单齿配体)的稀土金属配合物的发展及其在聚烯烃制备中的应用.这项工作旨在促进稀土金属催化剂在聚烯烃催化和金属有机催化领域的研究,为高端化、差异化聚烯烃聚合催化剂的制备提供新的设计思路和研究方法.  相似文献   

6.
富烯已被广泛应用于合成各种取代环戊二烯基、茚基和芴基金属配合物[1] .富烯的取代基对于它本身的反应性质以及由富烯所派生出的金属配合物的性质都起着重要的作用 .另外 ,富烯在手性配体及手性金属配合物的合成方面起着非常重要的作用 [2 ,3] ,仅就 6,6-二烷基富烯的加成反应而言 ,不但可以合成出多种烷基取代的手性金属配合物 [4 ] ,还可以引入杂原子而合成出手性配体 [5] .在研究 6-氨基富烯的加成反应时人们发现 ,由它不仅可以生成手性配体 ,而且其取代基上的氨基还可以与中心金属原子发生配位 [6 ] .最近 ,我们研究了 6-二甲氨基 - 6-…  相似文献   

7.
对双吡唑烷ⅥB金属羰基配合物的电化学特性进行了系统研究,结果表明,吡唑环上的取代基极大的影响双吡唑烷ⅥB金属羰基配合物金属中心的峰电位E1/2。给电子代取代基增强配体的配位能力且使金属中心的E1/2减小,而吸电子取代基减弱配体的配位能力使金属中心的E1/2增大。  相似文献   

8.
金属-配体间的配位作用是超分子化学中最重要的相互作用之一,寡聚吡啶配体可以与许多过渡金属离子配位,形成具有独特磁、光物理和电化学性质的过渡金属配合物,因此联三吡啶配体过渡金属配合物性能研究引起化学家的广泛关注。本文系统综述了联三吡啶配体及其衍生物的组装策略及其过渡金属配合物的光化学与光物理性能,包括单极、二极及多极配体以及由这类配体组装得到的各种拓扑结构的单核、多核过渡金属配合物,如线型金属寡聚物、金属聚合物、金属大环化合物、有机金属树枝状化合物等,并介绍这些配合物在该领域研究和应用前景。  相似文献   

9.
本文合成了四种具苯并咪唑基配体:邻-二[N,N'-二(2'-苯并咪唑甲基]氨基]-反式-环己烷(OCTB)及其三种系列物,分别与[Cu^Ⅰ(CH~3CN)~4]ClO~4]反应制得了相应的双核Cu(Ⅰ)配合物1-4。经元素分析、红外光谱和核磁共振等表明自由配体及其相应配合物均符合组成。紫外-可见光谱表明配合物1-4具有氧合性能, 它们的无色DMF溶液吸氧后呈绿色,在可见区700nm附近出现宽吸收峰, 用抗环血酸还原成无色, 如此可循环3-4次。用气体吸收测量方法算得配合物1-4于DMF中氧合反应平衡常数, △H°和△S°。研究表明, 配体苯并咪唑N上空间位阻大不利于氧合; 斥电性取代基可增加配位原子的电负性, 使中心原子Cu(Ⅰ)上电子密度增加, 有利于氧合。在不同溶剂中氧合速度大小为: DMF>DMSO>Py。  相似文献   

10.
2-巯基苯并咪唑钐配合物在天然橡胶中防老化作用的研究   总被引:4,自引:0,他引:4  
以2-巯基苯并咪唑为配体,制备了一种新型稀土钐配合物.采用红外光谱、热重分析等方法研究了钐配合物对天然橡胶硫化胶热氧老化过程的影响,探讨了钐配合物对天然橡胶硫化胶防老化作用的机理.红外光谱分析结果表明添加2-巯基苯并咪唑钐配合物的天然橡胶硫化胶经热氧老化后,氧化产物的生成量明显减少.2-巯基苯并咪唑钐配合物对天然橡胶硫...  相似文献   

11.
N-Heterocyclic carbenes (NHCs) are widely used as ligands in catalysis by transition metal complexes. The catalytic activity of transition metal NHC complexes is much higher than that of the transition metal complexes bearing the phosphine and nitrogen-containing ligands. They show excellent catalytic performance in different transformations of the organic compounds, especially in the carbon—carbon and carbon—element bond forming reactions. Palladium NHC complexes are very efficient catalysts for the cross-coupling reactions. On the other hand, nickel is less expensive and regarded as a promising alternative to palladium and, therefore, it attracts increasing attention from the researches. The present review is focused on the recent advances in the synthesis of N-heterocyclic carbene complexes of nickel and palladium and their application in catalysis of cross-coupling reactions of organic, organoelement and organometallic compounds with organic halides.  相似文献   

12.
郭明  孔亮  厉欣  邹汉法 《化学学报》2003,61(1):95-99
将微透析(microdialysis)高效液相色谱法(high performance liquid chromatography,HPLC)联用技术应用于定量研究超氧化物歧化酶(superoxide dismutase)与组氨酸和组氨酸-金属离子配合物的相互作用。实验结果表明: Cu2Zn2SOD酶不仅与组氨酸,而且还可以与组氨酸-Co(Ⅱ)和组氨酸-Ni(Ⅱ)相互 作用,Cu2Zn2SOD酶中的部分Cu(Ⅱ)和Zn(Ⅱ)被诱导和置换出来,并相应地影响了 酶的活性;组氨酸-金属离子配合物的作用比组氨酸强,酶活性降低也更明显;酶 中结合的外来金属离子的量比从酶上被诱导和顶替下来的金属离子的量要少,说明 在溶液中有脱辅基酶的存在。  相似文献   

13.
铜-(N-正十二碳酰双甘肽)配合物模拟SOD研究   总被引:2,自引:0,他引:2  
合成一种新的SOD模拟物带功能基的长链铜()氨基酸配合物N-正十二碳酰双甘肽合铜[Cu(C12-Gly-Gly)]和二-(N-正十二碳酰双甘肽合铜)[Cu(C12-Gly-Gly)2].用脉冲辐解法测定了其SOD样活性,发现Cu(C12-Gly-Gly)2的SOD样活性基本接近于天然SOD,达到了整体模拟SOD的效果.  相似文献   

14.
Three imine-based metal complexes, having no overlap in terms of their compositions, have been simultaneously generated from the self-sorting of a constitutional dynamic library (CDL) containing three amines, three aldehydes, and three metal salts. The hierarchical ordering of the stability of the three metal complexes assembled and the leveraging of the antagonistic and agonistic relationships existing between the constituents within the constitutional dynamic network corresponding to the CDL were pivotal in achieving the sorting. Examination of the process by NMR spectroscopy showed that the self-sorting of the FeII and ZnII complexes depended on an interplay between the thermodynamic driving forces and a kinetic trap involved in their assembly. These results also exemplify the concept of “simplexity”—the fact that the output of a self-assembling system may be simplified by increasing its initial compositional complexity—as the two complexes could self-sort only in the presence of the third pair of organic components, those of the CuI complex.  相似文献   

15.
This review is aimed at updating the recent development on the metal complexes bearing azolate‐containing chelates that have received a growing attention from both the industrial and academic sectors. Particular emphasis is given to the luminescent metal complexes, for which tridentate and multidentate bonding interactions give rise to both higher ligand field strength and better rigidity versus their bidentate counterparts—consequently, this is beneficial to the chemical stability and emission efficiency needed for applications such as organic light‐emitting diodes and bio‐imaging. Their basic designs involve chelates, such as monoanionic 6‐azolyl 2,2′‐bipyridine, dianionic 2,6‐diazolylpyridine, and 2‐azolyl‐6‐phenylpyridine, and the core metal ion spanning from main group elements, such as GaIII and InIII, to the late transition metal ions such as RuII, OsII, IrIII, and PtII and even the lanthanides. Furthermore, the great versatility of these azolate chelates for assembling the robust and emissive metal complexes, provides bright prospect in future optoelectronic investigations.  相似文献   

16.
Three imine‐based metal complexes, having no overlap in terms of their compositions, have been simultaneously generated from the self‐sorting of a constitutional dynamic library (CDL) containing three amines, three aldehydes, and three metal salts. The hierarchical ordering of the stability of the three metal complexes assembled and the leveraging of the antagonistic and agonistic relationships existing between the constituents within the constitutional dynamic network corresponding to the CDL were pivotal in achieving the sorting. Examination of the process by NMR spectroscopy showed that the self‐sorting of the FeII and ZnII complexes depended on an interplay between the thermodynamic driving forces and a kinetic trap involved in their assembly. These results also exemplify the concept of “simplexity”—the fact that the output of a self‐assembling system may be simplified by increasing its initial compositional complexity—as the two complexes could self‐sort only in the presence of the third pair of organic components, those of the CuI complex.  相似文献   

17.
Mimicking the Superoxide Dismutase Enzyme (SOD), several imidazolato-bridged copper(II)-zinc(II) complexes were prepared, characterised by IR spectroscopy and their SOD enzyme activity was determined. 2,2′-Bipyridine, 2,2′:6′,2″-terpyridine and tris(2-aminoethyl)amine molecules were used on both metal sides, as coordinating ligands. The complex, containing the 2,2′:6′,2″-terpyridine ligand on copper side has the smallest SOD activity, which indicates the importance of the rigidity of the copper complex in SOD activity.  相似文献   

18.
The absorption maxima, molar absorptivities, infrared spectra, compositions, formation constants, and pH dependence of amino acid—chloranil complexes have been determined with purified chloranil The n-π charge-transfer interaction depends on the presence of an unprotonated amino group; pH 9 is optimal for complex formation, but once formed, the complex is stable in a highly acidic medium and may be quantitatively extracted by hexanol. The molar absorptivities of the chloranil complexes of glycine, iminodiacetic acid, NTA, EDTA, DTPA and TTHA were measured. There is a linear relationship between the logarithm of the molar absorptivities of their chloranil complexes and the number of carboxylic groups in the molecule. There is an inverse linear relationship between the molar absorptivities of chloranil—metal—EDTA complexes and the logarithm of the stability constants of the EDTA chelates. This leads to a new method of determining the stability constants of complexes involving a nitrogen-donating group.  相似文献   

19.
Macrocyclic polyethers and their complexes   总被引:8,自引:0,他引:8  
The most important, and almost unique, property of the macrocyclic polyethers (“crown compounds”) is their tendency to form complexes with alkali metal salts and salts with similar cations. Such complexes are held together by electrostatic attraction between the cation and the negative end of the C? O dipoles. The stability of the polyether complexes depends primarily upon how well the cation fits into the polyether ring; other factors are the charge density of the cation and—in solution—the solvating power of the medium. Cyclic polyethers have been successfully employed, inter alia, in experiments with ionic compounds in organic solvents and in studies of ion transport in biological systems.  相似文献   

20.
刘春光 《物理化学学报》2011,27(7):1661-1665
采用量子化学密度泛函理论(DFT)结合有限场(FF)的方法对一系列含有Pt―Pt键金属配合物的电子结构和二阶非线性光学(NLO)性质进行了理论计算. 结果表明改变共轭配体对Pt―Pt键影响不大. 由配体到Pt―Pt金属基团的电荷转移强度随配体增长而变大. 金属配合物静态一阶超极化率随配体的增长而增大, 配合物电荷的改变基本不影响这类化合物的二阶NLO性质. 具有相对长的共轭配体的配合物IId具有最大的二阶NLO响应. 含时密度泛函理论(TD-DFT)计算表明配合物IId的二阶NLO响应来自于混有配体到金属的配体内的π→π*电荷转移跃迁的贡献.  相似文献   

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