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1.
由吡咯和葡萄糖取代苯甲醛直接缩合制备了两种葡萄糖取代卟吩:四(邻位乙酰葡萄糖氧代苯基)卟吩和四(间位乙酰葡萄糖氧代苯基)卟吩,进一步金属化合成了4种葡萄糖金属卟啉:氯化四(邻位乙酰葡萄糖氧代苯基)卟吩合铁、氯化四(间位乙酰葡萄糖氧代苯基)卟吩合铁、氯化四(邻位四乙酰葡萄糖氧代苯基)卟吩合锰和氯化四(间位乙酰葡萄糖氧代苯基)卟吩合锰.它们的结构由紫外-可见光谱、核磁共振和元素分析证实.研究了这些葡萄糖取代金属卟啉对亚碘酰苯常温常压下氧化环己烷反应的催化作用.研究结果表明,4种糖基金属卟啉催化下的环己烷反应产率和反应速率都比一般金属卟啉高.反应动力学分析表明,在常温常压下,糖基金属卟啉催化下的环己烷氧化反应具有酶催化反应的动力学关系.  相似文献   

2.
由吡咯和葡萄糖取代苯甲醛直接缩合制备了两种葡萄糖取代卟吩:四(邻位乙酰葡萄糖氧代苯基)卟吩和四(间位乙酰葡萄糖氧代苯基)卟吩,进一步金属化合成了4种葡萄糖金属卟啉:氯化四(邻位乙酰葡萄糖氧代苯基)卟吩合铁、氯化四(间位乙酰葡萄糖氧代苯基)卟吩合锰。它们的结构由紫外-可见光谱、核磁共振和元素分明,4种糖基金属卟啉催化下的环己烷反应的催化作用。研究结果表明,4种糖基金属卟啉催化下的环己烷反应产率和反应  相似文献   

3.
阳卫军 《分子催化》2012,(4):314-321
以苯乙烯、环己烯和反式二苯乙烯为烯烃底物,以双氧水、叔丁基过氧化氢和异丙苯过氧化氢为氧化剂,以苯环上对位和邻位氯取代的四苯基金属卟啉为仿生催化剂,对烯烃的催化环氧化反应进行了对比研究.讨论了不同氯取代位的四苯基金属卟啉对烯烃环氧化性能的影响.实验结果表明,在没有助催化剂存在下,邻位氯代的四(2,6-二氯苯基)铁(锰)卟啉对烯烃的环氧化具有优异的催化性能,烯烃底物的转化率和环氧选择性都比对位氯代的四苯基铁(锰)卟啉高,且反应条件温和.其中FeⅢ(TDCPP)Cl的催化性能最好,环氧化选择性最高,催化氧化苯乙烯时,环氧苯乙烷的选择性达到了90.4%.相同金属离子不同配体的金属卟啉传递氧原子的能力为TDCPP>T(p-Cl)PP>TPP.氧化剂的结构对环氧化物的选择性有较大影响.过氧键连有吸电子基团的异丙苯过氧化氢对环氧化物的选择性最高.根据实验结果,对金属卟啉催化环氧化机理进行了分析.  相似文献   

4.
在氯合,-5,10,15,20-四苯基卟吩合锰(Ⅲ)[TPPMn(Ⅲ)Cl]催化下,带有不同取代基的亚碘酰苯对环己烷的充氧化反应与TPPFe(Ⅲ)Cl催化的结果不同,取代基的电子效应和立体效应对羟化产物(环己醇)的产率无线性相关性,而对氯代产物(氯代环己烷)的产率有良好线性相关性.比较了苯亚碘酸二醋酐、苯亚碘酸单对甲苯磺酸酐和邻、间、对亚碘酰苯甲酸及邻亚碘酰苯甲酸酯的结构对环己烷充氧化反应的影响,表明了它们的结构相似性.  相似文献   

5.
《分子催化》2012,26(4)
以苯乙烯、环己烯和反式二苯乙烯为烯烃底物,以双氧水、叔丁基过氧化氢和异丙苯过氧化氢为氧化剂,以苯环上对位和邻位氯取代的四苯基金属卟啉为仿生催化剂,对烯烃的催化环氧化反应进行了对比研究.讨论了不同氯取代位的四苯基金属卟啉对烯烃环氧化性能的影响.实验结果表明,在没有助催化剂存在下,邻位氯代的四(2,6-二氯苯基)铁(锰)卟啉对烯烃的环氧化具有优异的催化性能,烯烃底物的转化率和环氧选择性都比对位氯代的四苯基铁(锰)卟啉高,且反应条件温和.其中FeⅢ(TDCPP)Cl的催化性能最好,环氧化选择性最高,催化氧化苯乙烯时,环氧苯乙烷的选择性达到了90.4%.相同金属离子不同配体的金属卟啉传递氧原子的能力为TDCPP〉T(p-Cl)PP〉TPP.氧化剂的结构对环氧化物的选择性有较大影响.过氧键连有吸电子基团的异丙苯过氧化氢对环氧化物的选择性最高.根据实验结果,对金属卟啉催化环氧化机理进行了分析.  相似文献   

6.
朱申杰  张春豪 《化学学报》1988,46(5):478-482
在氯合5,10,15,20-四苯基卟吩合铁(III)[TPPFe(III)Cl]催化下, 带有不同取代基的亚碘酰苯和亚碘酰苯的衍生物作充氧化剂对环己烷进行了仿生单充氧化反应的研究.取代亚碘酰苯中对位取代基的电子效应和间位取代基的电子及立体效应对氧化产物环己醇的产率有良好线性相关性. 亚碘酰苯的衍生物苯亚碘酸二醋酐与苯亚碘酸单对甲苯磺酸酐对环己烷的充氧化能力和邻、间、对亚碘酰苯甲酸与邻亚碘酰苯甲酸酯相似, 环己醇产率接近零. 从而提出亚碘酰苯甲酸及邻亚碘酰苯甲酸酯存在分子内或分子间I(oh)oco成键结构的论点.  相似文献   

7.
在氯合5,10,15,20-四苯基卟吩合铁(Ⅲ)[TPPFe(Ⅲ)Cl]催化下,带有不同取代基的亚碘酰苯和亚碘酰苯的衍生物作充氧化剂对环己烷进行了仿生单充氧化反应的研究.取代亚碘酰苯中对位取代基的电子效应和间位取代基的电子及立体效应对氧化产物环己醇的产率有良好线性相关性.亚碘酰苯的衍生物苯亚碘酸二醋酐与苯亚碘酸单对甲苯磺酸酐对环己烷的充氧化能力和邻、间、对亚碘酰苯甲酸与邻亚碘酰苯甲酸酯相似,环己醇产率接近零.从而提出亚碘酰苯甲酸及邻亚碘酰苯甲酸酯存在分子内或分子间I(OH)OCO成键结构的论点.  相似文献   

8.
配位负载金属卟啉的合成及催化氧化环已烷的性能研究   总被引:1,自引:0,他引:1  
合成了三种与咪唑配体键合的新型载体,并通过其与四苯基卟啉铁和卟啉锰配位得到了改性的负载金属卟啉催化剂。讨论了它们在催化氧化环己烷反应中的稳定性、活性等,结果表明配位负载方式明显提高了金属卟啉的稳定性,其中硅胶配位负载锰卟啉还具有较高的活性。  相似文献   

9.
合成了三种与咪唑配体键合的新型载体,并通过其与四苯基卟啉铁卟啉锰配位得到了改性的负载金属卟啉催化剂。讨论了它们在催化氧化环己烷反应中的稳定性,活性等,结果表明本位负载方式明显提高了金属卟啉的稳定性,其中硅胶配置负载锰卟啉还具有较高的活性。  相似文献   

10.
金属卟啉的电化学性质与其催化氧化α-蒎烯性能的关系   总被引:2,自引:0,他引:2  
 采用循环伏安法对一系列四苯基金属卟啉的电化学氧化还原性质进行了研究,考察了四苯基金属卟啉的第一还原电位与其催化氧化α-蒎烯性能的关系. 结果表明,各四苯基金属卟啉催化空气氧化α-蒎烯转化率的大小顺序为 TPPMnⅢCl>TPPCoⅢCl>TPPFeⅢCl>TPPCuⅡ≈TPPNiⅡ≈TPPZnⅡ,除TPPCoⅢCl外,基本与其第一还原电位的大小顺序一致. 随着卟啉环上取代基供电子能力的减弱,各取代基铁卟啉和锰卟啉的第一还原电位E1值均逐渐减小,表现在催化体系中是它们越容易被还原而引发反应,催化氧化α-蒎烯的转化率逐渐升高. 四苯基铁卟啉和锰卟啉的第一还原电位E1与其卟啉环上对位取代基常数σ*之间均有良好的线性关系.  相似文献   

11.
For preparing a berberine-sensitive electrode, 5,10,15,20-tetrakis[2-(2,3,4,6-tetraacetyl-beta-D-glucopyranosyl)-1-O- phenyl]porphyrin (T(o-glu)PPH2) was synthesized from the reaction of pyrrole with ortho-acetylglycosylated benzaldehyde by Lindsay's method. The electrode based on T(o-glu)PPH2 with an optimized membrane composition exhibits Nernstian response to berberine in the concentration range 2.4 x 10(-7)-5.0 x 10(-3) mol L-1, with a pH range from 3.9 to 10.2, and a fast response time of 30 s. The electrode shows fair selectivity towards berberine with respect to common co-existing species. T(o-glu)PPH2 shows better potentiometric response characteristics comparing to chloro[5,10,15,20-tetrakis[2-(2,3,4,6-tetraacetyl-beta-D- glucopyranosyl)-1-O-phenyl]-porphinato]-manganese (MnT(o-glu)PPCl) and better selectivity towards berberine than tetraphenylporphyrin (TPPH2). The effect of the composition of the electrode membrane has been studied and the experimental conditions optimized. The contents of berberine in pharmaceutical tablets were determined by direct potentiometry and the results agreed with values obtained by the pharmacopoeia method.  相似文献   

12.
In this paper, the synthesis of a novel ionophore, chloro[5,10,15,20-tetrakis[2-(2,3,4,6-tetraacetyl-beta-D-glucopyranosyl)-1-O-phenyl]porphinato]manganese (MnT(o-glu)PPCl), and its application as a neutral carrier for a PVC membrane electrode are described. The MnT(o-glu)PPCl-based PVC membrane electrode shows a potentiometric responses to SCN- over a concentration range of 3.4 x 10(-7) - 1.0 x 10(-1) mol L(-1) with a Nernstian slope and a response time of 20 s. The electrode exhibits an anti-Hofmeister selectivity toward SCN- with respect to common coexisting anions. As active materials, MnT(o-glu)PPCl shows better selectivity toward SCN- than chloro(tetraphenylporphinato)manganese (MnTPPCl). The effect of the electrode membrane compositions has been studied and the experimental conditions were optimized. The electrode was applied to the determination of SCN- in body fluids with satisfactory results.  相似文献   

13.
An attempt has been made to prepare terephthalic acid(TPA) by solvent-free oxidation of p-xylene(PX) with air over tetra(pchlorophenylporphinato) manganese chloride(T(p-Cl)PPMnCl) and cobalt acetate.The co-catalysis between T(p-Cl)PPMnCl and Co(OAc)2 has been discovered under solvent-free conditions.TPA yield could be increased significantly when T(p-Cl)PPMnCl and Co(OAc)2 were used together.The addition of T(p-Cl)PPMnCl into the reaction mixture over Co(OAc)2 significantly accelerated the rate-determining step of the oxidation process of PX to TPA.The effect of temperature on reaction was also investigated.  相似文献   

14.
Tetra(carboxymethylenoxyphenyl)porphines which are soluble in bases are prepared by hydrolysis of the ethyl esters of tetra(carboxymethylenoxyphenyl)porphines. The starting ethyl esters of the tetra(carboxymethylenoxyphenyl)porphines were synthesized by alkylation of tetra(oxyphenyl)porphines with ethylchloroacetate, as well as by condensation of pyrrole with ethyl esters of formylphenoxyacetic acids.See [1] for Communication 4.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1373–1377, October, 1989.  相似文献   

15.
合成了6种不同大小的烷基取代的四中位(邻烷基)苯基卟啉T_(O-R)PPH_2及其高铁络合物T_(O-R)PPFeCl(R=CH_3,C_2H_5,n-C_3H_7,i-C_3H_7,n-Bu,t-Bu),除R=CH_3外,其它5种是文献未曾报道过的新化合物。测定了它们的核磁共振谱、红外及电子光谱,并讨论了它们的结构与光谱性质的关系.  相似文献   

16.
李和平  郭灿城 《有机化学》2000,20(5):830-832
在还原剂维生素C存在下,将4-氨基苯甲醛与吡咯在丙酸中缩合得到5,10,15,20-中位-四(4-氨基苯基)卟吩,操作简单,产率高于文献方法。  相似文献   

17.
The biomimetic oxidation of caffeine with hydrogen peroxide using metalloporphyrins as catalysts, which are known to be good biomimetic models of cytochrome P450 enzymes, is investigated. The two manganese porphyrins tested, chloro[5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrinato]manganese(III), [Mn(TDCPP)Cl], and chloro [5,10,15,20-tetrakis(pentafluorophenyl)porphyrinato]manganese(III), [Mn(TPFPP)Cl], afford high conversions of caffeine for all substrate/catalyst molar ratios. Selectivity was found to be dependent on the catalyst employed, and a new spiro racemic compound is described and fully characterized in the solid state from X-ray diffraction studies.  相似文献   

18.
Syntheses, optical spectroscopy, potentiometric studies, and electronic structural calculations are reported for two classes of conjugated (porphinato)metal oligomers that feature a meso-to-meso ethyne-bridged linkage topology. One set of these systems, bis[(5,5'-10,20-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]ethyne (DD), 5,15-bis[[5'-10',20'-bis[3,5-di(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]ethynyl]-10,20-bis[3,5-di(9-methoxy-1,4,7-trioxanonyl)phenyl]porphinato)zinc(II) (DDD), and 5,15-bis[[15' '-(5'-10',20'-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]-[(5' '-10' ',20' '-bis[3,5-di(9-methoxy-1,4,7-trioxanonyl)phenyl]porphinato)zinc(II)]ethyne]ethynyl]-10,20-bis[3,5-di(9-methoxy-1,4,7-trioxanonyl)phenyl]porphinato)zinc(II) (DDDDD), constitute highly soluble analogues of previously studied examples of this structural motif having simple 10,20-diaryl substituents, while a corresponding set of conjugated oligomers, [(5-10,20-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]-[(5'-15'-ethynyl-10',20'-bis[10,20-bis(heptafluoropropyl)porphinato)zinc(II)]ethyne (DA), 5,15-bis[[5'-10',20'-bis[3,5-di(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]ethynyl]-10,20-bis(heptafluoropropyl)porphinato]zinc(II) (DAD), and 5,15-bis[[15' '-(5'-10',20'-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]-[(5' '-(10' ',20' '-bis(heptafluoropropyl)porphinato)zinc(II)]ethyne]ethynyl]-10,20-bis[3,5-di(9-methoxy-1,4,7-trioxanonyl)phenyl]porphinato)zinc(II) (DADAD), features alternating electron-rich and electron-poor (porphinato)zinc(II) units. Electrooptic and computational data for these species demonstrate that it is possible to engineer conjugated oligomeric structures that possess highly delocalized singlet (S1) excited states yet manifest apparent one-electron oxidation and reduction potentials (E1/20/+ and E1/2-/0 values) that are essentially invariant with respect to those elucidated for their constituent monomeric precursors.  相似文献   

19.
Abstract— The antibacterial photodynamic effects of uncharged ( o -tetrahydroxyphenyl porphine [THPP], m -THPP and p -THPP), cationic (5,10,15,20-tetra[4- N -methylpyridyllporphine [TMPyP]) and anionic (5,10,15,20-tetra[4-sulfonatophenyl porphine] [TPPS4]) porphines on Staphylococcus aureus and Escherichia coli bacteria inactivation were examined. The results show that uncharged porphines provoked antibacterial photodynamic activity on S. aureus, and also on E. coli in the presence of the membrane-disorganizing peptide polymixin B nonapeptide (PMNP). The TMPyP compound was highly photoactive toward gram-positive bacteria but only marginally effective on gram-negative cells, whereas TPPS4 showed no activity on either gram-positive or gram-negative bacteria. The photoactivity of TMPyP is due to the electrostatic attraction between the positively charged sensitizer molecule and the negatively charged membrane of the gram-positive target cells. For TPPS4, the inactivity toward gram-positive bacteria is due to electrostatic repulsion between the charged sensitizer molecule and the cell membrane. For gram-negative bacteria, the inactivity is conceivably due to preferential (electrostatic) binding to the positively charged PMNP, which is an adjuvant for membrane disorganization, but has no effect on cell viability. For hydrophobic sensitizers, the photoactivity depends on the state of aggregation. The extent of deaggregation of the different THPP isomers was determined by fluorescence measurements of bound sensitizers and could be positively correlated with their photoinactivation capacity. We conclude that the structure-activity relationships of these porphines are affected by their net charge and by aggregation.  相似文献   

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