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1.
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.
本文综述了近几年来手性金属卟啉配合物在主客体化学、立体催化及光电化学领域的性能研究成果。分析了在主客体化学中手性卟啉作为分子识别反应主体所具有的结构特征;介绍了模拟生物大分子的功能时手性卟啉所反映出的识别机制;评述了手性卟啉对苯乙烯及其衍生物的环丙烷化、羟基化及氨化等催化反应中所展示出的对映选择性和催化稳定性;概括了手性卟啉配合物在模拟植物光合成反应和制作新型光学材料方面所具有的光电性能。最后总结了手性卟啉研究成果的应用范围,并展望了手性卟啉在催化氧化方面的研究和发展方向。  相似文献   

3.
卟啉及卟啉衍生物的应用   总被引:4,自引:0,他引:4  
近年来,卟啉及卟啉衍生物在显色反应、分子识别、催化合成反应等领域中有很广泛的应用。文章就卟啉及卟啉衍生物在分析化学、生命科学和化学合成方面的研究发展作一简要介绍,并提出卟啉化合物今后的发展方向。  相似文献   

4.
卟啉及其衍生物的π电子共轭平面结构,使其具有独特的光电性能和良好的热稳定性,在仿生、催化、医学及材料科学等领域得到了广泛的应用。随着自组装技术的不断发展,其在制备功能化超薄膜方面表现出显著的优越性。本文重点介绍了卟啉及其衍生物自组装超薄膜的制备方法,并总结了近年来卟啉自组装膜在光电转换方面的研究进展。  相似文献   

5.
四(4-硝基苯基)卟啉和四(4-氨基苯基)卟啉的合成   总被引:21,自引:1,他引:20  
四(4氨基苯基)卟啉(TAPP)是含有4个反应活性基团的卟啉衍生物,可在模拟某些生物过程或氧化还原反应的树枝状或簇状分子中作为富电子中心,也可直接用来制备光电器件或作为光电功能聚合物的功能单体和交联剂,因此,TAPP的合成研究具有重要意义[1]....  相似文献   

6.
杨新国张登  唐瑞仁 《化学进展》2009,21(12):2595-2604
以卟啉基为中心核的树枝状化合物具有特殊的物理、化学及光电性能,其中一个重要特性是具有优良的能量和电子转移性能,近年来研究人员合成了一系列新型的以卟啉为中心核的树枝状化学物,这些化合物在许多领域有着潜在的应用前景。本文综述了近几年来以卟啉基为中心核的树枝状化合物的最新研究结果,介绍了一些具有代表性的新型化合物,概述了部分化合物的合成方法及性能,这些化合物由于其结构改变带来的性能变化,分别在光收集材料、发光材料、光动力学疗法、催化剂、传感器等领域有着潜在的应用前景。最后展望了此类化合物的发展方向。  相似文献   

7.
卟啉类化合物分子光电器件研究进展   总被引:2,自引:1,他引:1  
分子电子器件是未来分子电路的微电子元件,已成为有机功能纳米材料研究的热点。 卟啉类化合物的π共轭体系表现出的独特光电性能和良好的热稳定性,使其作为光电器件、模拟生物酶、分子识别和传感材料在材料化学、医学、生物化学和分析化学等领域展现出良好的应用前景,由于卟啉分子平面结构的易修饰性,常用卟啉化合物组装单元来构建功能化的卟啉光电器件。 本文综述了卟啉类化合物的特点及其在光电器件中的应用进展。  相似文献   

8.
用于光动力治疗的四苯基卟啉衍生物研究进展   总被引:1,自引:0,他引:1  
四苯基卟啉(TPP)衍生物的重要用途之一是用于光动力治疗(PDT)来破坏肿瘤组织.本文综述了近年来可用于光动力治疗的四苯基卟啉(TPP)衍生物的合成.通过对TPP衍生物进行官能团修饰,可以改善其物理、化学及生物性质,从而合成出可能用于PDT的卟啉衍生物.  相似文献   

9.
新型氨基酸尾式卟啉及莫锌配合物的合成与表征   总被引:11,自引:0,他引:11  
金属卟啉配合物作为主体分子对氨基酸酯及其衍生物的分子识别研究是当今卟啉仿生化学的重要课题[1~6].这一领域的研究成果在生物传感器的研制,癌症的诊断和治疗,模拟含卟啉生物大分子的功能以及在生物大分子构象和类型的识别研究中具有潜在的应用价值[7].  相似文献   

10.
金属卟啉配合物作为主体分子对氨基酸酯及其衍生物的分子识别研究是当今卟啉仿生化学的重要课题[1-6]。这一领域的研究成果在生物传感器的研制,癌症的诊断和治疗,模拟含卟啉生物大分子的功能以及在生物大分子构象和类型的识别研究中具有潜在的应用价值[7]。氨基酸是弱的电子授体,将其连接在卟啉分子中可以改变卟啉配体的受授性质,同时氨基酸尾式卟啉更接近天然卟啉。另外,氨基酸是蛋白质的主要组成部分,在蛋白质的生物合成过程中,对氨基酸及其衍生物的识别是关键的一步。酰胺转移t-RNA合成酶对氨基酸表现出极为专一的立…  相似文献   

11.
Abstract

The kinetics of Zn2+ and Zn(OH)+ incorporation into and the kinetics of the acid catalyzed removal of Zn(II) from twelve water-soluble, sulfonated derivatives of tetraphenylporphyrin with alkyl or halogen groups in the para, ortho or di-ortho positions were investigated. While the incorporation reactions showed little dependence on porphyrin basicity, the Zn-P (P = porphyrin derivative) acid solvolysis reactions were faster the higher the basicity of the free base (H2-P) compound. Equilibrium constants for the formation of cadmium porphyrins decreased with an increase in porphyrin basicity. The predeformed tetrakis(4-sulfonatophenyl)-β-octabromo-porphyrin reacted with Zn2+ about 103 times faster than porphyrins of similar basicity. These results indicate how substituents on the phenyl and beta-pyrrole rings influence the solution chemistry of water soluble porphyrins.  相似文献   

12.
A series of coronenetetraimide (CorTIm)‐centered cruciform pentamers containing multiporphyrin units, in which four porphyrin units are covalently linked to a CorTIm core through benzyl linkages, were designed and synthesized to investigate their structural, spectroscopic, and electrochemical properties as well as photoinduced electron‐ and energy‐transfer dynamics. These systems afforded the first synthetic case of coroneneimide derivatives covalently linked with dye molecules. The steady‐state absorption and electrochemical results indicate that a CorTIm and four porphyrin units were successfully characterized by the corresponding reference monomers. In contrast, the steady‐state fluorescence measurements demonstrated that strong fluorescence quenching relative to the corresponding monomer units was observed in these pentamers. Nanosecond laser flash photolysis measurements revealed the occurrence of intermolecular electron transfer from triplet excited state of zinc porphyrins to CorTIm. Femtosecond laser‐induced transient absorption measurements for excitation of the CorTIm unit clearly demonstrate the sequential photoinduced energy and electron transfer between CorTIm and porphyrins, that is, occurrence of the initial energy transfer from CorTIm (energy donor) to porphyrins (energy acceptor) and subsequent electron transfer from porphyrins (electron donor) to CorTIm (electron acceptor) in these pentamers, whereas only the electron‐transfer process from porphyrins to CorTIm was observed when we mainly excite porphyrin units. Finally, construction of high‐order supramolecular patterning of these pentamers was performed by utilizing self‐assembly and physical dewetting during the evaporation of solvent.  相似文献   

13.
Schiff-base (SB) derivatives of Ni(II) and Cu(II) porphyrins endowed with various amine functions (R−NH2),n-butylamine,p-anisidine andm-nitroaniline have been prepared from corresponding formyl porphyrins. Protonation studies of these SB derivatives reveal a marked red shift of the optical absorption bands in the visible region relative to the unprotonated imines. The magnitude of the observed red shifts in the protonated derivatives, (SBH+) are found to depend on the electron-withdrawing or electron-donating nature of the R group of the amines. The results of the optical absorption,1H NMR, EPR, and cyclicovoltammetric studies are illustrative of the fact that protonation of the SB derivatives results in a localized positive charge, in the periphery of the porphyrin (p) system. The dibenzo-18-crown-6 interspersedbisporphyrin schiff bases have been prepared fromtrans 4,4′-diamino dibenzo-18-crown-6 and formyl porphyrins. The protonation of these SB derivatives is found to proceed in a concerted fashion. The cation complexation studies by the crown ether entity in thebisporphyrin systems have been investigated using optical absorption, magnetic resonance and electrochemical methods. The redox characteristics of the protonated dimeric SB porphyrins reveal that the first oxidation step involves a two-electron transfer reaction. This is important in view of their possible usage in multielectron transfer reactions of biological and catalytic interest.  相似文献   

14.
Studies on the design and synthesis of receptor molecules capable of selectively binding and transporting substrates (neutral, anionic and cationic) is currently being pursued to develop artificial membranes permeable to the bound species. Expanded porphyrin systems by virtue of increased cavity size and aromatic nature are capable of binding a variety of substrates depending on the nature of the porphyrin and the cavity size. Recently there are a number of reports on the use of expanded porphyrins as molecular receptors for various substrates. Specifically, expanded porphyrins such as sapphyrins and rubyrins in their protonated form bind a variety of anionic and neutral substrates and it has been shown that they act as carriers for transporting different ionic and neutral species. Additionally, expanded porphyrins find their application as MRI contrasting agents and as sensitizers for photodynamic therapy. In this review, an attempt has been made to discuss molecular receptor properties in the solid and solution phases of two expanded porphyrins, sapphyrin and rubyrin which are 22 and 26 electron systems respectively. Furthermore, the synthesis, binding and transport properties of core modified expanded porphyrin systems are also highlighted.  相似文献   

15.
A methodology is reported for the regioselective nitration of the phenyl groups of Halterman porphyrin, using NaNO2. These nitro-porphyrins can be reduced to aminoporphyrins and then N-dimethylated to give new optically active porphyrins. Applications to the asymmetric epoxidation of styrene derivatives by H2O2 to give optically active epoxides (ee up to 60%) and hydroxylation of alkanes to give optically active secondary alcohols (ee up to 69%) were carried out in organic solvents (dichloromethane/methanol) using chiral iron and manganese porphyrins as catalysts.  相似文献   

16.
Main-group complexes are shown to be viable electrocatalysts for the H2-evolution reaction (HER) from acid. A series of antimony porphyrins with varying axial ligands were synthesized for electrocatalysis applications. The proton-reduction catalytic properties of TPSb(OH)2 (TP=5,10,15,20-tetra(p-tolyl)porphyrin) with two axial hydroxy ligands were studied in detail, demonstrating catalytic H2 production. Experiments, in conjunction with quantum chemistry calculations, show that the catalytic cycle is driven via the redox activity of both the porphyrin ligand and the Sb center. This study brings insight into main group catalysis and the role of redox-active ligands during catalysis.  相似文献   

17.
One of the applications of cationic porphyrins is their use in microbial photodynamic inactivation (PDI). For this purpose there is a constant quest for new cationic photoactive derivatives. In this work, we synthesized and fully characterized a new porphyrin 3a and the corresponding cationic derivative 3b. The results presented here show that meso-tetrakis(pentafluorophenyl)porphyrin (TPPF20, 1) can be used as scaffold to prepare different soluble compounds with interesting photophysical properties.  相似文献   

18.
A series of meso-furyl porphyrins with four different porphyrin cores (N4, N3S, N2S2 and N3O) were synthesized and characterized. The comparison of NMR, optical and fluorescence properties of meso-furyl porphyrins with porphyrins with six-membered aryl groups indicates that electronic properties of porphyrins were changed drastically on the introduction of furyl groups at meso positions. The maximum shifts in spectral bands were observed for meso-furyl porphyrins with N2S2 core. On protonation, the absorption bands of meso-furyl porphyrins were further red shifted. All these changes were ascribed to the possibility of more planarity of the meso-furyl porphyrins due to the small size of the furyl groups which results in extending the π-delocalisation of the porphyrin ring in to the furyl groups.  相似文献   

19.
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   

20.
In this work, we report the synthesis, spectroscopic characterization, and theoretical analysis of a linearly conjugated pentacene‐fused porphyrin dimer and cross‐conjugated quinone‐fused dinaphtho[2,3]porphyrins. These multichromophoric systems display non‐typical UV‐visible absorptions of either porphyrins or pentacenes/quinones. UV‐visible, emission and magnetic circular dichroism (MCD) spectroscopy suggest strong electronic interactions among the multichromophores in the system. DFT calculations revealed the delocalization of the HOMOs and LUMOs spanning the entire dimer and linker assembly. The pentacene‐fused porphyrin dimer is significantly more stable than both the corresponding pentacene and the heptacene derivatives. The availability of these huge π‐extended and electronically highly interactive multichromophoric systems promises unprecedented electronic and photophysical properties.  相似文献   

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