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1.
刘鼎  成林  何军  郭玉  刘运美 《化学通报》2018,81(9):780-791
卟啉化学是有机化学研究中不可或缺的一个方向。由于卟啉在结构上具有一个大的共轭体系,从而具有典型的芳香性。其具有优异的光电性能、独特的光动力治疗作用、高效的催化活性,并且广泛存在于血红素、叶绿素、维生素B_(12)、过氧化氢酶等有机生物分子中,所有这一切都吸引着科学家们进行深入研究。本文从取代卟啉、缩合卟啉以及扩环卟啉三个方面分别讨论了卟啉的研究进展,通过列举一系列经典的反应以及卟啉衍生物,总结了卟啉衍生物的合成方法及其发展方向。另外,文中还对于卟啉的一些特殊物理、化学和光电性质,做了重点介绍。本文旨在为卟啉的研究者们提供参考。  相似文献   

2.
血红蛋白在生物体内起着储存和运输氧分子、催化氧化有机物、分解过氧化氢和传递电子等作用.钴卟啉能可逆地结合氧可作为血红蛋白的模拟化合物,因此,研究钴卟啉与含氮配体的轴配反应有重要意义[1-3].  相似文献   

3.
卟啉钴分子筛的制备,表征和催化性能的研究   总被引:3,自引:2,他引:3  
用液-固相分步合成法将新型四卤四甲基卟啉诱捕在经Co^2+交换的NaX分子筛超笼内,利用索式提取器洗净分子筛外表面吸附的卟啉后,采用UV-Vis、IR、SEM、DTA、X射线衍射分析、吸附等手段对诱捕在超笼内的卟啉予以表征。进一步对比研究了卟啉、分子筛和诱捕卟啉分子筛的催化性能。结果表明,卟啉与分子筛结合后,催化活性大大提高。  相似文献   

4.
卟啉化合物的共振能   总被引:3,自引:0,他引:3  
袁履冰  张田林 《有机化学》1986,6(4):286-290
具有芳香性的卟啉环的共振能是卟啉类化合物的重要结构参数,据此可以讨论卟啉的光谱和化学反应性能等问题。本文根据分享键能(Contributing Bond Energy)的概念,对复杂分子卟啉的键能进行了计算。采用分享键能和键解离能(Bond Dissociation Energy)的差值,计算了某些卟啉化合物的共振能。计算方法简便,计算结果与以前文献报道的以及实验值符合。  相似文献   

5.
对烷氧基苯基苯并卟啉的新法合成及性能研究   总被引:3,自引:0,他引:3  
采用先接链后合环密闭熔融新方法,合成了5个系列25种对烷氧基苯基苯并卟啉,通过紫外,红外,质谱和元素分析等手段进行了表征,初步研究了10种新型卟啉的性能。  相似文献   

6.
将金属次卟啉二甲酯用作叔丁基过氧化氢(TBHP)氧化苯乙烯制苯甲醛的催化剂。 考察了催化剂、氧化剂用量、反应温度、时间、溶剂和不同金属次卟啉二甲酯[M(DPDME)]对苯乙烯转化率及苯甲醛选择性的影响,初步探索了反应机理。 结果表明,金属次卟啉二甲酯能够顺利地选择性催化氧化苯乙烯生成苯甲醛。 以0.002 mmol锰次卟啉二甲酯[ClMn(DPDME)]为催化剂,0.4 mmol TBHP为氧化剂,1 mmol苯乙烯为底物,5 mL CH3CN/H2O(体积比4∶1)为溶剂,反应温度75 ℃,常压反应20 h,苯乙烯的转化率达到98.3%,苯甲醛的选择性为92.7%。  相似文献   

7.
研究了甲基丙烯酸八氟戊酯 乙烯基咪唑共聚物 (PFIm)与 5 ,1 0 ,1 5 ,2 0 四 (邻 三甲基乙酰胺苯基 )钴卟啉 (TPPCo)复合膜的氧络合百分率随环境湿度和时间的变化 ,讨论了钴卟啉不可逆氧化的机理、动力学 ,及钴卟啉与氧络合的寿命 .空气中的水分子进攻与氧络合的钴卟啉 ,生成过氧化氢自由基和三价钴卟啉 ,是钴卟啉失去与氧络合能力的主要原因 .发现PFIm的憎水性可抑制由水分子引起的钴卟啉的不可逆氧化反应 ,可显著延长钴卟啉与氧络合的寿命 ,从而使含氟的PFIm TPPCo膜与氧络合的寿命要比甲基丙烯酸辛酯 乙烯基咪唑共聚物 (POIm)与钴卟啉复合膜的寿命长  相似文献   

8.
异卟啉研究进展   总被引:1,自引:0,他引:1  
异卟啉是通过改变卟啉大环结构而得到的卟啉类似物。由于具有独特的结构和性能,如阴离子识别、稳定异常价态金属离子、Mbius芳香性、构建新型超分子体系、电子转移以及近红外荧光等特性,异卟啉已引起人们越来越多的兴趣。本文简要介绍了异卟啉研究的意义,异卟啉的命名以及分类,并重点介绍了N-错位卟啉、扩展卟啉和氧化卟啉原等异卟啉的研究现状及最新进展。同时对咔咯、氧化咔咯原、卟啉烯、核修饰卟啉、亚卟啉和杯吡咯等异卟啉的发展现状及其性能作了简要概述。通过对异卟啉化合物研究,可得到很多普通卟啉难以实现的性能,并有望在相关领域获得实际应用。本文在介绍异卟啉研究的同时,还尝试翻译了一些相关专业术语。  相似文献   

9.
铜卟啉,钒氧卟啉的合成   总被引:1,自引:0,他引:1  
王煜  何明威 《应用化学》1996,13(6):67-68
铜卟啉、钒氧卟啉的合成王煜,何明威,王军强,武靖荣(山西大学化学系太原030006)关键词卟啉,铜卟啉,钒氧卟啉,合成合成金属卟啉,通常是先合成卟啉,再将卟啉与金属盐反应,经柱色谱分离后得到目标化合物[1].本文报道以酚为溶剂,使吡咯、芳香醛和乙酸铜...  相似文献   

10.
在交联聚苯乙烯微球表面实现苯基卟啉的同步合成与固载   总被引:2,自引:0,他引:2  
以键合有对羟基苯甲醛(HBA)的交联聚苯乙烯(CPS)微球HBA-CPS、苯甲醛和吡咯为反应物, 采用Adler方法, 实现了苯基卟啉(PP)在CPS表面的同步合成与固载, 制得了固载有苯基卟啉的微球PP-CPS. 研究了卟啉同步合成与固载过程的影响因素, 同时进行了微球PP-CPS与钴盐的配合反应, 制备了固载有钴卟啉(CoP)的功能微球CoP-CPS, 初步考察了其对分子氧氧化乙苯的催化活性. 实验结果表明, 在苯基卟啉同步合成与固载的反应过程中, 催化剂的酸性与溶剂的极性是两个主要的影响因素, 使用强极性溶剂与pKa在2.8~3.4范围的酸, 微球PP-CPS表面的苯基卟啉固载量高. 微球CoP-CPS对分子氧氧化乙苯的反应具有明显的催化活性.  相似文献   

11.
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   

12.
Abstract

Various supramolecular assemblies based on expanded porphyrins building blocks containing sulfur and/or selenium in the core, formed through multiple non-covalent hydrogen bonding interactions are highlighted. Specifically, modified expanded porphyrins such as 22 π sapphyrins, 26 π rubyrins, and 34 π octaphyrins self assemble in solid state through C–H…O, C–H…N, C–H…S, C–H…Se, C–H…π, and C–H…Cl interactions to form dimeric, oligomeric, and three dimensional networks. Furthermore, the supramolecular networks promoted by trapped solvent molecules such as nitrobenzene and bound anions such as chloride or trifluoroacetate through noncovalent interactions will be discussed.  相似文献   

13.
Incisive modulation of the intermolecular hardness between metalloporphyrins and O2 can lead to the identification of promising catalysts for oxygen reduction. The dependency of the electrocatalytic reduction of O2 by metalloporphyrins on the nature of the central metal yields a volcano‐type curve, which is rationalized to be in accordance with the Sabatier principle by using an approximation of the electrophilicity of the complexes. By using electrochemical and UV/Vis data, the influence of a selection of meso‐substituents on the change in the energy for the π→π* excitation of manganese porphyrins was evaluated allowing one to quantitatively correlate the influence of the various ligands on the electrocatalysis of O2 reduction by the complexes. A manganese porphyrin was identified that electrocatalyzes the reduction of oxygen at low overpotentials without generating hydrogen peroxide. The activity of the complex became remarkably enhanced upon its pyrolysis at 650 °C.  相似文献   

14.
The core N?H units of planar porphyrins are often inaccessible to forming hydrogen‐bonding complexes with acceptor molecules. This is due to the fact that the amine moieties are “shielded” by the macrocyclic system, impeding the formation of intermolecular H‐bonds. However, methods exist to modulate the tetrapyrrole conformations and to reshape the vector of N?H orientation outwards, thus increasing their availability and reactivity. Strategies include the use of porpho(di)methenes and phlorins (calixphyrins), as well as saddle‐distorted porphyrins. The former form cavities due to interruption of the aromatic system. The latter are highly basic systems and capable of binding anions and neutral molecules via N?H???X‐type H‐bonds. This Review discusses the role of porphyrin(oid) ligands in various coordination‐type complexes, means to access the core for hydrogen bonding, the concept of conformational control, and emerging applications, such as organocatalysis and sensors.  相似文献   

15.
赵晓红  张韫宏 《化学通报》2007,70(7):558-560
分析了中性条件下在水溶液及盐溶液中系列双亲卟啉随其浓度连续变化的紫外-可见吸收光谱。结果表明,在中性条件下不同侧链取代基对双亲卟啉的聚集行为有很大影响,盐的加入导致卟啉的聚集形态发生改变,初步解释了影响卟啉聚集的原因。  相似文献   

16.
An efficient procedure is described for catalyst recycling and easy product isolation in alkene epoxidation with hydrogen peroxide catalyzed by water-soluble iron(III) porphyrins in environmentally benign and ambient temperature ionic liquids.  相似文献   

17.
卟啉是一类重要的大环化合物,广泛存在于自然界和生命体中,具有广泛的应用。 由于自由卟啉化合物的化学稳定性差,天然卟啉通常在特定的天然大分子(多肽)环境中发挥其特性,因此,人们研究开发了多种担体,固载化卟啉和金属卟啉,大大拓展了其应用范围。 本文综述了文献报道的卟啉及金属卟啉的常用固载载体、常用的固载方法、以及固载型卟啉化合物在催化和传感器等领域的最新应用进展,展望了卟啉的固载化和固载型卟啉的应用前景。  相似文献   

18.
Iron and manganese porphyrins containing 2,6-di-tert-butylphenyl groups (R4PFeCl and R4PMnCl) have been synthesized to be further immobilized on silica gels via various spacers. The activity of these porphyrins in the oxidation of alkanes and alkenes by hydrogen peroxide has been studied. 2,6-Di-tert-butylphenol groups decrease the catalytic activity of porphyrins in oxidation processes.  相似文献   

19.
Porphyrins and metallopophyrins have attracted the attention of chemists for the past 100 years or more owing to their widespread involvement in biology. More recently, synthetic porphyrins and porphyrin-like macrocycles have attracted the attention of researchers due to their diverse applications as sensitizers for photodynamic therapy, MRI contrasting agents, and complexing agents for larger metal ions and also for their anion binding abilities. The number of π-electrons in the porphyrin ring can be increased either by increasing the numberof conjugated double bonds between the pyrrole rings or by increasing the number of heterocyclic rings. Thus, 22π sapphyrins, 26π rubyrins, 30π heptaphyrins, 34π octaphyrins and higher cyclic polypyrrole analogues containing 40π, 48π, 64π, 80π and 96π systems have recently been reported in the literature. These macrocycles show rich structural diversity where normal and different kinds of inverted structures have been identified. In this review, an attempt has been made to collect the literature of the inverted porphyrins and expanded porphyrins reported until December 2001. Since themeso aryl expanded porphyrins have tendency to form both inverted and non-inverted structures more emphasis has been given tomeso aryl expanded porphyrins.  相似文献   

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