共查询到20条相似文献,搜索用时 31 毫秒
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采用苯酐-尿素路线合成了八羧基铜酞菁(CuPc)和十二羧基双核铜酞菁(Cu2Pc2), 研究了两种铜酞菁对巯基乙醇的催化活性, 推测出了双核铜酞菁的催化机理, 并考察了pH值、催化剂浓度和温度对双核铜酞菁催化氧化巯基乙醇的影响. 实验发现, 单核铜酞菁对巯基乙醇无催化活性, 而双核铜酞菁对巯基乙醇有较高的催化活性; 双核铜酞菁的催化活性在pH=11时最大; 催化活性随催化剂浓度和温度升高而提高; 此催化反应为吸热反应. 相似文献
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双核茂金属催化剂催化聚合反应进展 总被引:2,自引:0,他引:2
综述了双核茂金属化合物的研究进展及其在烯烃和极性单体聚合方面的应用及双核茂金属化合物的合成及性能研究;并对双核催化剂的作用机理、催化剂结构与性能的关系也做了介绍。 相似文献
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稀土双核配合物的合成与磁性 总被引:1,自引:0,他引:1
稀土离子存在于许多磁性材料中,但至今稀土双核配合物的合成及磁性研究很少,建立磁性-结构间的关系对新型分子磁性材料的设计有重要意义。稀土双核配合物的磁性研究也为研究f轨道参与磁相互作用提供第一手材料。我们曾合成了一系列以氯冉酸二价阴离子为桥联配体的过渡金属双核配合物,本文合 相似文献
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Sven Wiesner Dr. Arne Wagner Dr. Elisabeth Kaifer Prof. Hans‐Jörg Himmel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10438-10445
We report on the first valence tautomeric dinuclear copper complex, featuring 2,3,5,6‐tetrakis(tetramethylguanidino)pyridine as a bridging redox‐active GFA (guanidino‐functionalized aromatic) ligand. The preferred electronic structure of the complex is massively influenced by the environment. In the solid state and in nonpolar solvents a paramagnetic, dinuclear CuII complex with a neutral GFA ligand is present. In polar solvents, the electronic structure changes to a diamagnetic, dinuclear CuI complex with a twofold‐oxidized GFA ligand. Using acetone as a solvent, both electronic structures are accessible due to a temperature‐dependent equilibrium between the two valence tautomeric complexes. Our results pave the way for a broader use of valence tautomeric transition‐metal complexes in catalytic reactions since anionic coligands can now be tolerated owing to the neutral/positively charged GFA ligand. 相似文献
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一种大环化合物的晶体结构及其双核铜配合物的酪氨酸酶活性研究 总被引:2,自引:0,他引:2
A ring-contracted form macrocycle, 29,30-dioxo-3,6,9,17,20,23,29,30-octaazapentacyclo[23,3,1,1^11,15,0^2,6,0^16,20]-triacontaneocta- 1 (28),9,11 (12), 13,15(30),23,25(29),26-ene (L) was synthesized by condensation of diethyltriamine with pyridine-1-oxide-2,6-dicarboxaldehyde. A porous three-dimensional layer structure in its crystal was formed by self-assembly through hydrogen bonds and π-π interaction. Its dinuclear copper(I) complex [Cu2L(MeOH)2]-(BF4)2*2H2O and dinuclear-copper(II) complex [Cu2L(MeOH)2](ClO4)4*2H2O were obtained and could oxidize catalytically four phenolic substrates hydroquinone, 2-methyl-hydroquinone, 2,6-di-tert-butylphenol and 2,6-dimethylphenol, in a mixture of methanol and acetonitrile (V : V, 4 : 1). The copper(I) complex reacted with dioxygen to form an oxygenated species as an initial active intermediate for oxidation of the phenols. Oxidation of the substrates by the copper(II) complex produced a copper(I) complex and the oxidation products of the substrates. 相似文献
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Dinuclear Copper Intermediates in Copper(I)‐Catalyzed Azide–Alkyne Cycloaddition Directly Observed by Electrospray Ionization Mass Spectrometry 下载免费PDF全文
Dr. Claudio Iacobucci Dr. Samantha Reale Prof. Jean‐François Gal Prof. Francesco De Angelis 《Angewandte Chemie (International ed. in English)》2015,54(10):3065-3068
The mechanism of the CuAAC reaction has been investigated by electrospray ionization mass spectrometry (ESI‐MS) using a combination of the neutral reactant approach and the ion‐tagging strategy. Under these conditions, for the first time, putative dinuclear copper intermediates were fished out and characterized by ESI(+)‐MS/MS. New insight into the CuAAC reaction mechanisms is provided and a catalytic cycle is proposed. 相似文献
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Electrocatalytic Water Oxidation by a Dinuclear Copper Complex in a Neutral Aqueous Solution 下载免费PDF全文
Xiao‐Jun Su Meng Gao Prof. Dr. Lei Jiao Prof. Dr. Rong‐Zhen Liao Prof. Per E. M. Siegbahn Prof. Dr. Jin‐Pei Cheng Prof. Dr. Ming‐Tian Zhang 《Angewandte Chemie (International ed. in English)》2015,54(16):4909-4914
Electrocatalytic water oxidation using the oxidatively robust 2,7‐[bis(2‐pyridylmethyl)aminomethyl]‐1,8‐naphthyridine ligand (BPMAN)‐based dinuclear copper(II) complex, [Cu2(BPMAN)(μ‐OH)]3+, has been investigated. This catalyst exhibits high reactivity and stability towards water oxidation in neutral aqueous solutions. DFT calculations suggest that the O? O bond formation takes place by an intramolecular direct coupling mechanism rather than by a nucleophilic attack of water on the high‐oxidation‐state CuIV?O moiety. 相似文献
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Cu2I2(PPh3)3·DMF(Ph=C6H5,DMF=HCON(CH3)2)是通过W2S4〔S2CN-(CH2CH2OH)2〕2,PPh3和CuI在CH2Cl2和DMF为溶剂,在室温条件下合成的晶体产物。其空间群为P21/c,晶胞参数:C57H52Cu2I2NOP3,a=15.863(5),b=19.619(7),c=18.232(4),β=109.53(2)°,V=5348(3)3,Z=4,Mr=1240.87,Dc=1.54g/cm3,μ(Mo-Kα)=20.66cm-1,F(000)=2472,对于I>3σ(I)的5954个衍射点,最终的R=0.046,Rw=0.069。晶体结构由二核铜化合物和溶剂DMF组成,两个Cu原子呈现不对称配位结构,DMF在三配位Cu原子的近邻,它的氧原子和配位PPh3的碳原子最近距离在3.32(2)-3.44(2),DMF参与晶体中对二核铜分子的结构和分子的堆积有明显的影响 相似文献
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HUANG Xi-He SHENG Tian-Lu XIANG Sheng-Chang FU Rui-Biao HU Sheng-Min LI Ya-Min WU Xin-Tao 《结构化学》2007,26(2)
The hydrothermal reaction of 1,2-dicyanobenzene with NaN3 in the presence of CuCl2, 2,2′-bipyridine and H2O affords a novel dinuclear copper(II)-ditetrazolate, [Cu(bpy)- (pdtz)]2 (Hpdtz = 5,5′-1,2-phenylene-ditetrazole, bpy = 2,2′-bipyridine). The pdtz ligand is generated in situ through Sharpless 2+3 cycloaddition reaction. Its crystal structure was deter- mined by single-crystal X-ray diffraction method. The crystal crystallizes in the monoclinic system, space group P21/n with a = 8.2096(16), b = 18.580(4), c = 11.838(2) , β = 103.12(3)o, V = 1758.5(6) 3, Z = 2, Mr = 863.83, Dc = 1.631 g/cm3, F(000) = 876 and μ = 1.272 mm-1. In this novel dinuclear structure, the pdtz ligand adopts a peculiar μ2-η1,η2 coordination mode. 相似文献
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本文合成了1个新的铜双核配合物[(CuI)(PMN)]2.2CH3CN(PMN=2、4-二氨基-5-氯苯基-6-乙基嘧啶),并且通过元素分析、红外、荧光、热重和单晶X-射线进行了表征。该配合物属三斜晶系,空间群P1,a=0.8100(16)nm,b=0.96950(19)nm,c=1.2049(2)nm,α=97.88(3)°,β=93.31(3)°,γ=94.14(3)°,V=0.933 8(3)nm3,Z=1,R=0.037 1。在配合物中,每个Cu(Ⅰ)离子与PMN配体的1个N原子和2个I原子配位,展示出三角几何构型。相邻的2个Cu(Ⅰ)离子通过碘原子相连形成双核铜配合物,并进一步通过氢键和I…I作用形成三维网状结构。 相似文献
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合成了以双吡唑桥联的双核铜配合物的3个同系物。利用吡唑-3,5-二(N-甲基甲酰胺)合硝酸铜双聚物的粉末ESR谱计算了g∥和g⊥。变温磁化率的实验数据拟合表明了它们均为有较强反铁磁性的化合物,用半经验分子轨道方法分析了它们的磁交换途径。 相似文献
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Reactivity of Dinuclear Copper(II) Complexes with N‐Salicylidene Glycine Schiff Bases as Carboxylesterase Models 下载免费PDF全文
Two phenoxo‐bridged dinuclear copper(II) complexes (Cu2L12, Cu2L22) with N ‐salicylidene glycine Schiff bases were prepared and evaluated their performance for catalyzing the hydrolysis of p‐nitrophenyl picolinate (PNPP). The observations reveal that the as‐prepared dinuclear copper(II) complexes exhibited better activity by two to three orders of magnitude rate enhancement in comparison with the autohydrolysis rate of PNPP. Chloro‐containing Cu2L22 aroused approximately three times kinetic advantage over chloro‐free Cu2L12 at pH 7.0, which is probably contributed to the electron‐withdrawing inductive effect of the 5′‐chloride group. Moreover, it was found that the pH‐responded kinetic behavior displayed an enzyme‐like property for the PNPP hydrolysis by the two complexes. 相似文献