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1.
杂多配合物异构体在马来酸环氧化反应中的催化活性   总被引:2,自引:0,他引:2  
马荣华  刘春涛  梁敏 《合成化学》2002,10(3):277-280
研究了20种杂多配合物异构体在马来酸环氧化反应中的活性,考察了反应时间、反应温度、催化剂用量等对马来酸环氧化反应的影响,选出了最佳反应条件。结果表明:所合成的杂多配合物异构体在催化以过氧化氢为氧化剂的马来酸环氧化反应中β异构体的催化活性高于α异构体。  相似文献   

2.
异羟肟酸过渡金属配合物对对氯甲苯催化氧化性能的研究   总被引:1,自引:1,他引:0  
考察了N-羟基-N-苯基苯甲酰胺的钴、锰和铜配合物在对氯甲苯液相氧化生成对氯苯甲酸反应中的催化性能.考察了反应温度、催化剂浓度、中心金属离子、以及助催化剂对催化氧化反应的影响,发现以钴配合物为催化剂,反应温度为140℃,催化剂浓度为1.0 × 10-3 mol·L-1为最佳反应条件.添加NaBr和四甘醇能促进对氯甲苯的...  相似文献   

3.
本文合成了N,N'-双(2'-羟基苯乙酮)缩乙二胺、N,N'-双(2'-羟基苯乙酮)缩1,2-丙二胺、N,N'-双(2'-羟基苯乙酮)缩1,3-丙二胺和N,N'-双(2'-羟基苯乙酮)缩邻苯二胺四种Schiff配体以及它们的锰(Ⅲ)配合物1,2,3和4.并考察了这四种锰(Ⅲ)配合物作为催化剂,催化以NaOCl为氧源环氧化苯乙烯和环己烯的反应的性能.同对考察了反应温度、助配体、NaOCl的浓度以及pH值对催化环氧化反应的影响.  相似文献   

4.
扼要介绍了模板反应的概念、类型,并举例介绍了在含氮大环金属配合物合成中的应用。  相似文献   

5.
本文合成了N,N’-双(2’-羟基苯乙酮)缩乙二胺、N,N’-双(2’-羟基苯乙酮)缩1,2-丙二胺、N,N’-双(2’-羟基苯乙酮)缩1,3-丙二胺和N,N’-双(2’-羟基苯乙酮)缩邻苯二胺四种Schiff配体以及它们的锰(Ⅲ)配合物1,2,3和4。并考察了这四种锰(Ⅲ)配合物作为催化剂,催化以NaOCl为氧源环氧化苯乙烯和环己烯的反应的性能。同时考察了反应温度、助配体、NaOCl的浓度以及pH值对催化环氧化反应的影响。  相似文献   

6.
合成和表征了两种对称的带冠醚环或吗啉环的Schiff碱Co(Ⅱ)配合物,将此配合物和表面活性剂形成的金属胶束,用于模拟水解金属酶催化BNPP水解。通过分析反应体系的特性吸收光谱,提出了BNPP催化水解反应的机理,据此建立了金属胶束催化BNPP水解的动力学数学模型。本文还讨论了配合物结构、反应体系温度以及胶束对催化BNPP水解的影响。  相似文献   

7.
张桦  曹美秋 《分子催化》1989,3(3):235-241
生物体内存在的各种金属卟啉配合物对酶的催化反应起着重要作用.它的储氧和载氧功能已被广泛研究,与血红蛋白一样,它对O_2、CO和NO等有络合活化能力.众所周知,CO和NO都是污染环境的有毒气体.近年来用金属卟啉和金属酞菁等含氮大环配合物将NO直接分解或用H_2,CO等作还原剂与NO进行氧还反应的研究十分活跃.我们在前报的基础上继续开展了CO常温氧化催化剂的研究.本工作是将四苯基卟啉钴(Co-TPP)负载于无定形的TiO_2载体上作为催化剂,研究了它在室温下对CO氧化的催化性能.确定了催化剂的最佳活化温度和再生条件,考察了反应温度和反应物浓度变化对活性的影响.求得CO常温氧化的速率方程.讨论了催化剂活性增强的主要原因.  相似文献   

8.
Schiff碱铜配合物模拟过氧化物酶的研究   总被引:9,自引:0,他引:9  
两种Schiff碱铜配合物首次作为过氧化物酶的模拟物用于催化过氧化氢氧化苯酚的反应;分析了配合物的特征光谱;研究了Schiff碱铜配合物的催化氧化机理,建立了催化氧化反应动力学数学模型;讨论了过氧化氢/催化剂摩尔比、体系温度、体系pH和胶束微环境对催化反应速率的影响.结果表明:这两种Schiff碱铜配合物在不同的反应条件下均表现出过氧化物酶催化的特征.  相似文献   

9.
Schiff碱配合物模拟酶催化性能的结构效应研究   总被引:3,自引:0,他引:3  
研究了新型Schiff碱双锰及双铁配合物在模拟酶催化PhIO单加氧化环己烷反应及被PhIO氧化破坏反应中的结构效应.结果表明,随着这些配合物的环内空腔逐渐增大,其抗氧化稳定性、催化活性及催化反应产率依次降低.配合物中最佳螯合环为五元环.  相似文献   

10.
四氮杂大环四烯镍(Ⅱ)配合物催化的化学振荡反应   总被引:2,自引:0,他引:2  
化学振荡反应是化学反应体系中某些状态量随时间或空间周期性变化。四氮杂大环配合物与存在生物体内的一些含有卟吩环的金属酶结构相似。目前,可以催化化学振荡反应的四氮杂大环配合物并不多,文献报道了一种具有C=N共轭双键的四烯型四氮杂大环配体(TIM)的Ni 的配合物可以催化BZ化学振荡反应[1-3]。然而以2,4,4,9.11,11一六甲基一1,5,8,12-四氮杂环十四一1,5, 8, 12一四烯(L)镍配合物[NiL(CIO4)2]这种具有四个孤立 C=N双键的四烯型四氮杂大环镍的配合物作为振荡反应催化…  相似文献   

11.
This study reports the synthesis method of a new aza-crown ether with an acetamide branch ligand, 2-(1,10-dioxa-4,7,13,16-tetraaza-cyclooctadec-4-yl)-acetamide (L), and determines the chemical composition of the cerium complex containing the aza-crown ether ligand by a new fluorescence spectrophotometric method. In the report, the cerium complex and its metallomicellar systems were used as catalysts in the hydrolysis of bis(4-nitrophenyl)phosphate ester (BNPP), and their catalytic activity was studied by the comparative method. The interaction between the metallomicelle and BNPP was proved by the fluorescence spectrum. The catalytic rate of BNPP hydrolysis was measured kinetically using the UV-Vis spectrophotometric method. The results indicated that the metallomicellar system of the anionic surfactant exhibited excellent catalytic function and relatively higher catalytic activity than that of the complex solution, the metallomicelle of nonionic and cationic surfactants, and the micelle provided an effective catalytic environment for the catalytic reaction. The experimental results also showed that the best acidity for the metallomicelle catalysis is pH 8.0, and the mono-hydroxy complex may be the real active species uaed as a catalyst in BNPP catalytic hydrolysis. The reaction mechanism was proposed on the basis of the research results.  相似文献   

12.
5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane (L) was synthesized and characterized. The kinetics of hydrolysis of bis(p-nitrophenyl)phosphate (BNPP) in the catalytic system containing macrocyclic ligand and cerium(III) was investigated. This catalytic system show high catalytic activity and better reproducibility and stability than other similar systems in the range of pH of around 5.6–7.2. The stoichiometry and spectral analysis showed that the real active species is the macrocyclic complex of cerium(III). Based on the analytical results of the specific absorption spectra, an intramolecular nucleophilic substitution mechanism for the catalytic hydrolysis of BNPP is proposed, a correlative kinetic mathematical model is established, and the corresponding thermodynamic and kinetic constants are calculated.  相似文献   

13.
A new metallomicellar system containing cerium(III), a macrocylic polyamine ligand, and the nonionic surfactant Brij35(polyoxyethylene(23) lauryl ether) was prepared and used as a catalyst in the hydrolysis of bis(4-nitrophenyl) phosphate (BNPP). Catalytic rate of the BNPP hydrolysis was measured kinetically using the UV-VIS spectrophotometric method. The results indicate that the metallomicellar system has relatively high stability and excellent catalytic function in the BNPP hydrolysis; also, the reaction rate of the BNPP catalytic hydrolysis increased by a factor of ca. 1 × 1010 compared to the BNPP spontaneous hydrolysis due to the catalytic effect of the active species and the local concentration effect of the micelles in the metallomicellar system. Experimental results also showed that the mono-hydroxy complex containing the macrocyclic polyamine ligand and cerium(III) is the real active species in the BNPP catalytic hydrolysis, and that the micelles provide a useful catalytic environment for the reaction. On basis of the research results, the reaction mechanism of BNPP catalytic hydrolysis has been proposed.  相似文献   

14.
A new metallomicellar system containing cerium ion (III), a macrocylic polyamine ligand and the hexadecyltrimethyl ammonium bromide (CTAB) was constructed and used as catalyst in the hydrolysis of bis(4-nitrophenyl) phosphate ester (BNPP). The catalytic rate of BNPP hydrolysis was measured kinetically with UV-vis spectrophotometric method. The results indicated that the metallomicellar system exhibited relatively high stability and excellent catalytic function in BNPP hydrolysis, and the reaction rate of the BNPP catalytic hydrolysis, compared with BNPP spontaneous hydrolysis, increased by a factor of ca. 1 × 108 due to the catalytic effect of the active species and the local concentration effect of the micelle in metallomicellar system. The experimental results also showed that the mono-hydroxy complex made of the macrocyclic polyamine ligand and cerium (III) is the real active species as catalyst in BNPP catalytic hydrolysis, and the micelles provide a useful catalytic environment for reaction. On the basis of the research results, the reaction mechanism of BNPP catalytic hydrolysis was proposed in this work.  相似文献   

15.
柳红军  周通  沈玉华  谢安建 《应用化学》2015,32(12):1410-1415
研究了Ce(Ⅲ)离子与巴比妥钠形成的配合物对双(对硝基苯基)磷酸酯(BNPP)的催化水解作用。 结果表明, Ce(Ⅲ)与巴比妥钠形成的配合物对BNPP的水解具有很高的催化活性,可使BNPP水解速率提高至自发水解时的1.52×108倍。 体系的pH值和温度对催化水解反应的影响,发现在温度为25 ℃和pH值为8.50的条件下,催化效果最佳。  相似文献   

16.
Two symmetrical double aza‐crowned Schiff base cobalt(II) complexes were synthesized and characterized, and the metallomicelle made up of the cobalt(II) complexes and surfactant, as mimic hydrolytic metalloenzyme, was used in catalytic hydrolysis of bis(4‐nitrophenyl) phosphate (BNPP). The analysis of specific absorption spectrums of the hydrolytic reaction systems indicated that key intermediates made up of BNPP and Co(II) complexes are formed in reaction processes of the BNPP catalytic hydrolysis. In this article, the mechanism of BNPP catalytic hydrolysis has been proposed based on the analytic result of specific absorption spectrum. A kinetic mathematical model, for the calculation of the kinetic parameter of BNPP catalytic hydrolysis has been established based on the mechanism proposed. The acid effect of reaction system, the structural effect of the complexes, the effect of surfactant micelles and the effect of temperature on the rate of BNPP hydrolysis catalyzed by the complexes have been discussed.  相似文献   

17.
It has been reported that three aza crowned Schiff base cobalt (II) complexes were synthesized and characterized, and the metallomicelle made up of the cobalt (II) complexes and surfactants(Brij35, CTAB, LSS), as mimic hydrolytic metalloenzyme, was used in catalytic hydrolysis of bis(4‐nitrophenyl) phosphate (BNPP). The analysis of specific absorption spectrums of the hydrolytic reaction systems indicated that key intermediates made up of BNPP and Co (II) complexes are formed in the reaction process of BNPP catalytic hydrolysis. The mechanism of BNPP catalytic hydrolysis proposed is based on the analytic result of specific absorption spectra. Based on the mechanism proposed, a kinetic mathematical model for the calculation of the kinetic parameter of BNPP catalytic hydrolysis has been established. The acid effect of reaction system, structure effect of the complexes, effect of temperature and effect of micelles on the rate of BNPP hydrolysis catalyzed by the complexes have been discussed.  相似文献   

18.
A macrocyclic ligand was synthesized and characterized. The kinetics of hydrolysis of bis(p-nitrophenyl)phosphate (BNPP) in the catalytic system containing macrocyclic ligand and praseodymium(III) was investigated. The analysis of specific absorption spectrums of the hydrolytic reaction systems indicated that key intermediates made up of BNPP and praseodymium(III) complexes are formed in the reaction process of BNPP catalytic hydrolysis. In this, the mechanism of BNPP catalytic hydrolysis proposed is based on the analytic result of specific absorption spectrum, and the corresponding kinetic constants are calculated. The results showed that the praseodymium(III) complexes as hydrolase mimics exhibit good catalytic activity and similar catalytic character to natural enzyme.  相似文献   

19.
冠醚化Schiff 碱配合物金属胶束催化BNPP水解动力学   总被引:3,自引:0,他引:3  
研究了两种新的冠醚化Schiff 碱过渡金属配合物与表面活性剂Brij35(聚氧乙烯(23)十二烷基醚)形成的金属胶束对BNPP(对硝基苯酚磷酸二酯)的催化水解反应. 探讨了催化反应机理, 建立了一种金属胶束催化BNPP水解的动力学数学模型; 计算了模拟酶催化反应的相关参数和表观活化能. 结果表明, 此类金属胶束作为模拟水解金属酶对BNPP水解反应表现出良好的催化活性.  相似文献   

20.
The design of artificial hydrolase has attracted extensive attention due to their scientific significance and potential application in the field of gene medicine and molecular biology. This work reports the catalytic activation of two aza-crown ether Ce(III) complexes and their metallomicelles as artificial hydrolase in bis(4-nitrophenyl) phosphate ester (BNPP) hydrolysis. The chemical composition of two complexes was determined by the fluorescence spectra and the mole ratio method for electronic absorption spectra. The bonding effect of BNPP and solubilizing effect of the complexes were proved by a method of fluorescence spectroscopy. The catalytic activity of different catalytic systems in BNPP hydrolysis was measured with UV-vis spectrophotometric method. These catalytic systems showed high catalytic activity for promoting BNPP hydrolysis at the almost physiological conditions. BNPP hydrolysis rate in these catalytic system is about 107- to 109-fold faster than that of the BNPP spontaneous hydrolysis in aqueous solution at the same conditions. The metallomicelle systems exhibited higher catalytic activity compared with the complex solution systems in BNPP hydrolysis, and hexadecyltrimethyl ammonium bromide micelle provides a useful catalytic environment for reaction. The acid effect of the catalytic system is ascribed to the formation of metal-bound hydroxide serving as a better kind of nucleophile.  相似文献   

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