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1.
二茂铁甲酰丙酮缩氨基硫脲金属配合物研究   总被引:4,自引:0,他引:4  
将二茂铁甲酰丙酮与硫代氨基脲在水 -乙醇介质中进行缩合反应 ,得金属有机多齿配体C5H5Fe C5H4COCH2 C(CH3 ) =NNHCSNH2 (简记作 Fc TS) ,该配体分别与 d-过渡金属 [Cu( )、Co( )、Ni( )、Mn( ) ]、 B族金属 [Zn( )、Cd( ) ]及主族金属 [Pb( ) ]乙酸盐反应 ,合成了分子式为 (Fc TS) 2 M(CH3 COO) 2 的 7个新型配合物。经元素分析、IR、UV- Vis,1 H HMR、摩尔电导及固体电导的测定对配合物组成、结构、波谱性质和导电性能进行了研究。  相似文献   

2.
Ten-membered heterocycles of the type PhN(PCl2){OC6H2(R)2 (μ-S(CH2))((R)2─C6H2O─)} (R = Me, iPr or tBu) have been prepared and their transition metal chemistry is explored. Functionalised phosphines react with transition metals to give interesting metallacycles. Several Group 6, ruthenium, platinum metals and novel titanium(IV) metallacycles have been structurally characterized.  相似文献   

3.
研究了高氧化态过渡金属盐(CuX2/L、FeX3/L,X=C1或Br;L =2,2′-联吡啶、N,N'-四甲基乙二胺、N,N,N′,N″,N″-五甲基二亚乙基三胺;CuSO4)催化甲基丙烯酸2-(N,N-二乙氨基)乙酯(DEAEMA)的自引发氧化聚合,利用气相色谱跟踪单体转化率、利用凝胶渗透色谱和多角激光光散射跟踪聚合...  相似文献   

4.
利用程序升温脉冲反应技术较系统地考察了担载型过渡金属催化剂上甲烷与乙烯同系聚合制丙烯和丙烷的反应,通过分步反应,即首先进行甲烷分解,然后引入了乙烯与甲烷分解产生的表面碳物种反应,可以克服甲烷与乙烯同系聚合物反应的动力学限制,使该反应能在较为温和的条件下进行,还系统地探讨了影响该反应的各种因素,结果表明,Pt,Co催化剂表现出较为优越的催化性能。  相似文献   

5.
烯烃活性聚合由于可以制备出预定分子量的窄分布聚合物,以及各种嵌段共聚物、末端功能化聚合物等而受到广泛关注.过渡金属催化的烯烃配位聚合反应活性高,催化剂性能可通过配体结构的修饰进行调节,聚合物微观结构易于调控,其活性聚合进一步拓展了对烯烃聚合物分子设计的手段,具有重要的意义.除了以钛、锆、钒等为金属中心的前过渡系催化剂之...  相似文献   

6.
IntroductionInformationonrelativereactiviticsofsuffocccarbonfromthcdecompositionofmethaneontransitionmetalcataIystspla}.simportantruleinourunderstandingthenatllreofeffcctiveutiliZaionofmethane.Asignificantamountofdataonthissubjecthavealread}'bccnaccumulatcd.Itx"asdiscovercdthatrcactiviticsofthesuffocecarbonstrongl}'dependonthcstructuralparameters-suchasthctyPcofsuffocecarbon.thestrengthofsurfacecarbon-metalinteractionsandthetendencyoftransformationamongthemll'2].0fspecialsarcthatthenatureofth…  相似文献   

7.
二茂铁基苯酰腙的d区金属螯合物的合成和表征   总被引:1,自引:0,他引:1  
二茂铁基苯酰腙与d区金属乙酸盐或氯化物在乙醇中反应,得到了6个新的螯合物,分子式为M(Fcbh)n[Fcbh=Fc—C=N—N=C-C_6H_5,Fc=C_5H_5—FeC_5H_4;M=Cr(Ⅲ)、Fe(Ⅲ)时,n=3;M=Mn(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)时,n=2]和Pd(Fcbh—H)_2Cl_2[Fcbh—H=Fc—C=N—NHCOC_6H_5]通过元素分析,红外光谱,H核磁共振谱和质谱,确定了螯合物的组成和结构。描述了二茂铁基苯酰腙配体与d区金属的两种不同的配位方式。  相似文献   

8.
Several mononuclear transition metal cations stabilized by acetonitrile molecules act as initiators for the polymerization of cyclopentadiene. The highest yield is reached with Cr, Mn, Fe, and Zn complexes, all of them in the oxidation state +II. The analogous V and Ni complexes, however, are completely or nearly inactive. In general, the observed activity of the examined monomeric complexes correlates well with the ligand field stabilization energy as a function of the number of d electrons for octahedrally coordinated transition metals in the oxidation state +II. The counter ions have a pronounced influence on the catalytic activity: the less coordinating they are, the higher is the activity of the cations. The reaction temperature also has a significant influence: above 50°C the complex activity is on decline, possibly due to initiator decomposition or com-petitive inhibition by dicyclopentadiene.  相似文献   

9.
用体积排除色谱方法研究了过渡金属Fe(Ⅲ)、Co(Ⅲ)、Cu(Ⅱ)、Ni(Ⅱ)的乙酰丙酮螯合物在四氢呋喃溶液中的加合和缔合行为。在溶液中乙酰丙酮钴(Ⅲ)以单个螯合物分子的形式存在,乙酰丙酮铜(Ⅱ)和乙酰丙酮铁(Ⅲ)与溶剂加合生成加合物,乙酰丙酮铁(Ⅲ)除加合物外还存在缔合度为2-10的多分散缔合物,乙酰丙酮镍(Ⅱ)水合物在四氢呋喃中产生了加合交换作用,同时存在缔合度为6左右的缔合物。色谱数据给出了螯合物、加合物及缔合物的相对含量。螯合物与相同分子量的聚苯乙烯相比,其保留体积的滞后以Ni相似文献   

10.
It has been made certain that thio-and oxy-diacetic acid hydrazidesare potential anticancer compounds.However,their ability to formcomplexes with transition metals and the properties of the complexes thusformed have not been studied.Employing a new potential anticancer ligand1,2-bis(thioacetic acid hydrazide)ethane prepared in our lab,along withligands oxydiacetic hydrazide and 1,2-bis(oxyacetic acid hydrazide)ethane,a series of 11 new first-row transition metal(M=Zn~(2+),Cu~(2+),Co~(2+),Ni~(2+))complexes with each of the above three ligands have been synthesizedand characterized by means of elemental analyses,IR,TG and X-raypowder diffraction.  相似文献   

11.
FeCl_3·6H_2O, NiCl_2, CuCl_2, ZnCl_2 and CrCl_3 have been incorporated into polyphenylquinoxaline by a new method. High-quality, flexible, glass-cast films have been obtained which exhibit increased glass transition temperature and excellent thermal stability. Moduli and tensile strengths of the metal-containing polyphenylquinoxaline films increase surprisingly at elevated temperature. Electrical resistivities of these films fall in the same order range as polyphenylquinoxaline alone. X-ray photoelectron spectroscopic study of metal-containing polyphcnylquinoxaiine films shows that all metals in these films are present in the ionic state, there is charge transfer between nitrogen of polyphenylquinoxaline and Cu~(2+), Zn~(2+) of CuCl_2, ZnCl_2 containing polyphenylquinoxaline films.  相似文献   

12.
徐元耀 《有机化学》1985,5(1):44-59
过渡金属化学已发展成为有机合成的重要方法,本文综述了它在精细有机合成中应用的一些进展。叙述了金属有机化合物作为亲电体与亲核试剂反应,金属有机化合物作为亲核体与亲电试剂反应,以及偶合和环化反应。应用这些反应可以巧妙地合成若干天然产物。  相似文献   

13.
碱金属原子簇的结构和稳定性   总被引:1,自引:0,他引:1       下载免费PDF全文
基于从体心立方碱金属晶体优化确立的多体展开势能函数,本文通过坐标优化研究了碱金属原子簇Xn(X=Li,Na,K,Rb,Cs)的结构和稳定性。发现:(1)Xn原子簇(n=4-21)倾向于形成畸变四面体结构单元,(Td)的密堆积,分子表面被三元环(D3h)所覆盖,其中X7-X15最优化结构中包含五角双锥X7(D5h)结构单元,具有区域五重对称轴;(2)“微观晶体碎片”的分层优化结果表明,体心立方、面心  相似文献   

14.
ABSTRACT

A new Schiff-base type oligocalix[4]arene containing two nitrile ligating sites at narrow rim was synthesized via a simple condensation reaction through a wide rim of the calixarene moiety. The extraction ability of the oligomer with selected alkali and transition metals is compared with its monomeric analogous. It has been observed that the oligomer 6 is not selective as compared to its analogae 2 and 3, but shows a remarkable high affinity towards toxic metal cations such as Cu2+, Hg2+ and Pb2+.  相似文献   

15.
制备了带羧基乳液浸渍纸.讨论了该浸渍纸对静态水溶液中重金属的离子交换性能,以及温度和pH值对离子吸附量的影响,发现该浸渍纸在用于水处理中具有良好的吸附性能和再生性能.  相似文献   

16.
In this paper the electronic configurations of n+1-decker transition metal sandwich com-plexes have been generally discussed by means of the structural rule of transition metalheterocarborans and the numbers of their valence bonding orbitals have been obtained as fol-lows: VBO = 6n + 3-6n + 5,which are not dependent on the properties of transition metal atoms and coordination rings.Then the results of EHMO quantum chemistry calculations of the model skeletons and cor-responding analyses on electronic configurations of actual molecules for double-, triple- andtetra-decker sandwich complexes have been discussed to verify the above formula.  相似文献   

17.
络合物稳定常数的计算   总被引:2,自引:0,他引:2  
本文介绍了计算络合物稳定常数的八种方法,它们是:1.lgK1=Az2/r+Bx±+C.2.两相似金属离子与一系列配位体络合时,lgK1间一的线性关系。3.两相似配位体与一系列金属离子络合时,lgK1间的线性关系。4.一系列相似配位体与同一金属离子络合时,lgK1与∑pKa间的线性关系。5.一系列相近z2/r的金属离子与同一配位体络合时lgK1与x±间的线性关系。6.一系列相近x的金属离子与同一配位体络合时lgK1与z2/r间的线性关系。7.金属离子随z2/r和x而变化的络合次序。8.∑pKa较大的配位体与z2/r较大的金属离子匹配,电负性较小的配位体与电负性大的金属离子匹配。  相似文献   

18.
Rosi Ketrin Katarina 《Talanta》2009,78(3):1043-990
On-line preconcentration and determination of transition and rare-earth metals in water samples was performed using a Multi-Auto-Pret system coupled with inductively coupled plasma-atomic emission spectrometry (ICP-AES). The Multi-Auto-Pret AES system proposed here consists of three Auto-Pret systems with mini-columns that can be used for the preconcentration of trace metals sequentially or simultaneously, and can reduce analysis time to one-third and running cost of argon gas and labor. A newly synthesized chelating resin, ethylenediamine-N,N,N′-triacetate-type chitosan (EDTriA-type chitosan), was employed in the Multi-Auto-Pret system for the collection of trace metals prior to their measurement by ICP-AES. The proposed resin showed very good adsorption ability for transition and rare-earth metal ions without any interference from alkali and alkaline-earth metal ions in an acidic media. For the best result, pH 5 was adopted for the collection of metal ions. Only 5 mL of samples could be used for the determination of transition metals, while 20 mL of samples was necessary for the determination of rare-earth metals. Metal ions adsorbed on the resin were eluted using 1.5 M nitric acid, and were measured by ICP-AES. The proposed method was evaluated by the analysis of SLRS-4 river water reference materials for trace metals. Good agreement with certified and reference values was obtained for most of the metals examined; it indicates that the proposed method using the newly synthesized resin could be favorably used for the determination of transition and rare-earth metals in water samples by ICP-AES.  相似文献   

19.
The modification of the electronic and chemical properties of Pt(111) surfaces by subsurface 3d transition metals was studied using density-functional theory. In each case investigated, the Pt surface d-band was broadened and lowered in energy by interactions with the subsurface 3d metals, resulting in weaker dissociative adsorption energies of hydrogen and oxygen on these surfaces. The magnitude of the decrease in adsorption energy was largest for the early 3d transition metals and smallest for the late 3d transition metals. In some cases, dissociative adsorption was calculated to be endothermic. The surfaces investigated in this study had no lateral strain in them, demonstrating that strain is not a necessary factor in the modification of bimetallic surface properties. The implications of these findings are discussed in the context of catalyst design, particularly for fuel cell electrocatalysts.  相似文献   

20.
13X分子筛去除水中重金属离子的研究   总被引:3,自引:0,他引:3  
以人工合成的13X型分子筛为吸附剂,研究了水中Pb2 、Cd2 和Cu2 在分子筛上的吸附行为,讨论了Pb2 、Cd2 和Cu2 共存条件下的竞争吸附,并考察了水中存在的Na 、Mg2 、Ca2 等离子对分子筛吸附去除重金属的影响.实验结果表明,13X分子筛对Pb2 、Cd2 和Cu2 3种离子的吸附符合Langmuir模型,最大吸附量分别为2.47mmol/L、2.0mmol/L和1.78mmol/L.在竞争吸附条件下,13X分子筛对3种重金属离子的选择性依次为pb2 >Cd2 >Cu2 .水中存在的Na 、Mg2 、Ca2 等对分子筛吸附重金属效率有一定的影响,其中Ca2 对Cu2 在分子筛上的去除影响最为显著.  相似文献   

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