T(4-CI-P)P的合成及其与铜反应的分光光度法研究

大杂环卟啉衍生物对某些金属离子具有高灵敏度(ε=2～5×10~5),近年来已引起人们的注意。目前报导用非水溶性卟啉化合物测定铜的有TPP、TF(COOEt)P、T[4-N(CH_3)_2]PP、T(4-NH_2)PP等。我们还合成了具有新型结构的α,β,γ,σ-四(4-氯苯基)     

金属四苯基卟啉-次氯酸钠模拟体系中芳醛氧化反应的研究

研究了以次氯酸钠为氧化剂在两相条件下芳香醛氧化反应中锰(III)-卟啉的催化性质, 在TPPMn(III)醋酸盐, TPPFe(III)氯化物, TPPCo(II)和TPPNi(II)催化剂中(四苯基卟啉, TPP), 前二个化合物呈现催化活性, 研究表明, OXO-金属卟啉的形成是反应的关键步骤。     

金属卟啉存在下芳醛氧化反应的研究

本文研究了在金属四苯基卟啉[Co(II)TPP,Fe(III)TPPCl,Mn(III)TPPCl,Zn(II)TPP,Cu(II)TP.TPP=四苯基卟啉]存在下,用氧气氧化芳醛的过程.测定了反应体系的吸氧动力学曲线;观察了氧化过程中金属卟啉的可见光谱的变化;研究了底物,金属卟啉在反应体系中的浓度以及溶剂等因素对反应的影响.结果发现,除能可逆键合分子氧的Co(II)TPP外,不具此种功能的Fe(III)TPPCl和Mn(III)TPPCl也能加速芳醛的氧化反应.然而,它们的催化作用是在金属四苯基卟啉与反应过程中积累起来的过酸作用,卟啉环遭到破坏后观察到的,此时可能形成了某种新的催化活性中心.金属卟啉本身对反应起抑制作用,它只是表观上的催化剂,其催化作用看来不应归结为对分子氧的活化.     

不对称酰胺基卟啉及其锌配合物的合成,表征及光谱研究

以CH2Cl2为溶剂,通过5-(4-氨基)苯基-10,15,20-三苯基卟啉(MATPP)与异烟酸直接反应得到一种不对称酰胺基卟啉配体(H2P),并合成了其锌配合物(ZnP),利用紫外-可见光谱、红外光谱、核磁共振氢谱、元素分析等测试方法对化合物的结构加以确认.同时,结合光谱法初步研究了卟啉的自聚合性质.研究表明,紫外-可见光谱显示了卟啉的J-聚合特征,荧光量子产率由于自聚合而降低.     

meso-5,10,15,20-四（取代2-噻吩基）卟啉及其配合物的合成与表征

用混合溶剂法合成了中位噻吩基取代的卟啉化合物：meso-四(2-噻吩基)卟啉 ，meso-四(4-溴-2-噻吩基)卟啉和meso-四(3-甲基-2-噻吩基)卟啉，产率达到36． 5％-39．3％，考察了溶剂的配比、反应温度、反应时间等因素对反应的影响，其 最佳反应条件为：溶剂配比：丙酸：乙酸：硝基苯：2：2(or3)：1；反应温度： 130~140t；反应时间：50-60min．研究了利用固相合成法合成上述卟啉化合物与过 渡金属盐形成配合物的配位反应，在40℃利用固相合成法合成了卟啉化合物与 Fe2' Fe~3+，CO~2+，Ni~2+，Mn~2+等过渡金属离子形成的配合物，产率为81．1 ％~87．6％．利用元素分析，UV-vis，m，'HNMR， HRMS对卟啉化合物及其配合物 进行了表征，利用TG-DTA研究了它们的热稳定性，利用EPR研究了它们的顺磁性．     

热处理温度对钴卟啉负载碳黑电催化剂的结构及氧还原性能的影响

制备了钴卟啉负载碳黑催化剂(CoTMPP/BP2000)用于燃料电池阴极氧还原反应. 利用循环伏安法研究了200～900 ℃热处理温度对催化性能的影响. 研究结果表明, 热处理能够提高CoTMPP/BP2000的催化活性, 热处理温度为900 ℃时, 催化剂的氧还原能力最好. 利用紫外-可见光谱、透射电镜、红外光谱、热重分析及X射线光电子能谱等手段研究了热处理温度对催化剂结构的影响. 结果表明, 热处理改变了催化剂的活性中心结构, 400 ℃以上热处理使催化剂中钴卟啉环的结构坍塌, Co—N4键断裂; 900 ℃高温下形成了稳定的Co—Nx—C结构, 新的活性位使催化剂的氧还原能力得到提高.     

在聚合物微球 GMA/MMA 表面同步合成与固载卟啉及固载化金属卟啉的催化氧化性能

 制备了甲基丙烯酸缩水甘油酯 (GMA) 与甲基丙烯酸甲酯 (MMA) 共聚微球 GMA/MMA, 并通过键合有对羟基苯甲醛 (HBA) 的改性微球 HBA-GMA/MMA 与苯甲醛 (或取代苯甲醛) 以及吡咯间的 Adler 反应, 实现了卟啉在共聚微球 GMA/MMA 表面的同步合成与固载, 制得了固载有苯基卟啉 (PP)、对氯苯基卟啉 (CPP)、对硝基苯基卟啉 (NPP) 的功能化微球 PP-GMA/MMA, CPP-GMA/MMA 和 NPP-GMA/MMA. 重点考察了影响卟啉同步合成与固载过程的因素. 制备了固载有钴卟啉的催化剂, 并以分子氧氧化乙苯为模型反应, 考察了催化剂的活性. 结果表明, 苯甲醛取代基的结构、催化剂的酸性和溶剂的极性对卟啉的同步合成与固载都有较大的影响; 钴卟啉催化剂对分子氧氧化乙苯反应具有较高的催化活性, 且当钴卟啉外环上含有强吸电子基团硝基时, 催化剂活性最高.     

烟酸修饰尾式卟啉的合成及其与人血清白蛋白的相互作用

合成了烟酸分子修饰的自由卟啉o-(niacin)C2O-T(3p-OCH3)PP、p-(niacin)C2O-T(3p-OCH3)PP及锌配合物o-(niacin)C2O-T(3p-OCH3)PPZn、p-(niacin)C2O-T(3p-OCH3)PPZn.经元素分析、紫外-可见光谱、核磁共振氢谱(1HNMR)、红外(IR)光谱等对结构进行了表征,并通过量子化学方法计算了锌卟啉的最低能量构型.实验结果表明:o-(niacin)C2O-T(3p-OCH3)PPZn中侧链烟酸基团处于卟啉环上方,烟酸基团中N原子与卟啉环中Zn2+存在着Zn―N间的分子内配位作用,而p-(niacin)C2O-T(3p-OCH3)PPZn中侧链烟酸基团处于卟啉环较远的位置,一个锌卟啉的中心Zn2+与另一个锌卟啉烟酸中N原子之间存在着Zn―N间的分子间配位作用.同时,为模拟金属卟啉的生物功能,采用荧光光谱滴定法测定了金属锌卟啉与人血清白蛋白相互作用的光谱性质.荧光光谱实验结果显示:金属锌卟啉与人血清白蛋白(HSA)之间发生了较强的静态荧光猝灭作用,反应机理是以氢键或van der Waals力结合反应.按照Stern-Volmer方程、Lineweaver-Burk双倒数方程分析和处理实验数据,得到了反应的猝灭常数、结合常数和热力学参数等.     

新型共价键连的富勒烯-卟啉化合物的合成与表征

为了构造一个具有有效电荷转移的给-受体体系,通过1,3-偶极加成反应,由5-[2-'(4″-醛基苯氧丙氧苯基)]-10,15,20-三苯基卟啉(H₂P-CHO)、肌氨酸和C₆₀首次合成了一种新的以共价键相连的富勒烯-卟啉配体(H₂P-C₆₀),同时用该配体制备了其锌配合物(ZnP-C₆₀),并用红外光谱、元素分析、电子光谱、核磁共振氢谱和质谱等方法进行了表征.     

meso-四(4-磺基苯基)卟啉在汞电极预吸附与铜、锌等离子形成络合物的伏安法研究

一般水溶性金属卟啉络合物要在溶液加热或有某种催化剂存在下才能形成。本文报道将乙酸缓冲液中的meso-四(4-磺基苯基)卟啉(TPPS_4)预先吸附于汞滴电极,取出电极,洗净,插入仅含Cu~(2+)的相同底液中,在单扫伏安图上就可得到Cu-TPPS_4络合物的还原峰。利用峰高可测定微量铜以及研究络合物的电化学行为。同样,在氨性底液中,吸附了卟啉的汞滴电极插入含Cd~(2+)、Zn~(2+)、Co~(2+)、Mn~(2+)等离子的溶液中,也可快速地得到相应的络合物还原峰。这是一个简便且重现性很好的形成和研究金属卟啉络合物的新方法。     

Molecular imprinting inside dendrimers

Synthetic hosts capable of binding porphyrins have been produced by a mixed-covalent-noncovalent imprinting process wherein a single binding site is created within cross-linked dendrimers. Two synthetic hosts were prepared, using as templates 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin and 5,10,15,20-tetrakis(3,5-dihydroxyphenyl)porphyrin. These two templates were esterified with, respectively, fourth- and third-generation Fréchet-type dendrons containing homoallyl end-groups. The resulting tetra- and octadendron macromolecules underwent the ring-closing metathesis reaction using Grubbs' Type I catalyst, RuCl(2)(P(C(6)H(5))(3))(2)(CHCH(2)C(6)H(5)), to give extensive interdendron cross-linking. Hydrolytic removal of the porphyrin cores afforded imprinted hosts whose ability to bind porphyrins with various peripheral substituents was investigated by UV-visible spectrophotometric titrations and size exclusion chromatography. The results indicate a high yield of imprinted sites that show high selectivity for binding of porphyrins capable of making at least four hydrogen bonds, but only a moderate degree of shape selectivity.     

Substituent effects on the site of electron transfer during the first reduction for gold(III) porphyrins

Gold(III) porphyrins of the type (P-R)AuPF(6), where P = 5,10,15,20-tetrakis(3,5-di-tert-butylphenyl)porphyrin and R is equal to H (1), NO(2) (2), or NH(2) (3) which is substituted at one of the eight beta-pyrrolic positions of the macrocycle, were investigated as to their electrochemistry and spectroelectrochemistry in nonaqueous media. Each compound undergoes three reductions, the first of which involves the central metal ion to give a Au(II) porphyrin or a Au(III) porphyrin pi-anion radical depending upon the nature of the porphyrin ring substituent. A similar metal-centered reduction also occurs for compounds 1, 3, and Au(III) quinoxalinoporphyrin, (PQ)AuPF(6) (4), where PQ = 5,10,15,20-tetrakis(3,5-di-tert-butylphenyl)quinoxalino[2,3-b]porphyrin, and these results on the three Au(III) porphyrins overturn the long held assumption that reductions of such complexes only occur at the macrocycle. In contrast, when a NO(2) group is introduced on the porphyrin ring to give (P-NO(2))AuPF(6) (2), the site of electron transfer is changed from the gold metal to the macrocycle to give a porphyrin pi-anion radical in the first reduction step. This change in the site of electron transfer was examined by electrochemistry combined with thin-layer UV-vis spectroelectrochemistry and ESR spectroscopy of the singly reduced compound produced by chemical reduction. The reorganization energy (lambda) of the metal-centered electron transfer reduction for (P-H)AuPF(6) (1) in benzonitrile was determined as lambda = 1.23 eV by analyzing the rates of photoinduced electron transfer from the triplet excited states of an organic electron donor to 1 in light of the Marcus theory of electron transfer. The lambda value of the metal-centered electron transfer of gold porphyrin (1) is significantly larger than lambda values of ligand-centered electron transfer reactions of metalloporphyrins.     

Rh(III) porphyrins as building blocks for porphyrin coordination arrays: from dimers to heterometallic undecamers

The coordination chemistry of a Rh(III) porphyrin building block was investigated with a view to the construction of heterometallic arrays of porphyrins. The Rh(III) porphyrin was found to coordinate methanol in the solid state and weakly in CDCl(3) solution. Crystallization afforded five coordinate pi stacked Rh(III) porphyrins. The distribution of products from reaction of Rh(III) porphyrin with DABCO, 4,4'-bipyridine, and 4,4'-bipyrimidine could be displaced toward dimeric species by silica gel column chromatography or recrystallization which served to remove excess ligand. Weak coordination to nitriles was observed, although it was sufficiently strong to organize a dimeric complex of 5,5'-dicyano-2,2'-bipyridine in the solid state. Complexes with 4,4'-bipyrimidine and 5,5'-dicyano-2,2'-bipyridine possess uncoordinated chelating nitrogen atoms. Larger heterometallic porphyrin arrays were assembled using a combination of Sn(IV) and Rh(III) porphyrin coordination chemistry. A Sn(IV) porphyrin acted as a core around which were coordinated two isonicotinate groups, carboxylic acid functionalized porphyrins, or porphyrin trimer dendrons. Rh(III) porphyrins were coordinated to pyridyl groups at the periphery of these entities. In this way an eleven porphyrin array, with four different porphyrin metalation states, was assembled. The diamagnetic nature of both the Rh(III) and Sn(IV) porphyrins, the slow ligand exchange kinetics on the NMR time scale, and tight ligand binding permitted the porphyrin arrays to be analyzed by two-dimensional (1)H NMR techniques.     

New anionic cobalt complexes using highly hindered bis-amides with varying donor abilities as ligands

Four potential tetradentate ligands of formulae 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)ethane (H(4)L(1), 1), 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)propane (H(4)L(2), 2), 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)benzene (H(4)L(3), 3) and 1,8-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)naphthalene (H(4)L(4), 4) have been prepared and the crystal structures of three of them (1, 3 and 4) determined by single crystal X-ray diffraction. The investigation of their complexing ability toward Co(II) afforded the compounds of formulae [Co(III)(L(3))Na(I)(H(2)O)(2)] (5), [Co(III)(L(n))Li(I)(H(2)O)2] with n = 1 (6), 2 (7) and 3 (8) and [Co(II)(L(4))Li(I)(2)] (9). Complexes 5-8 are square planar Co(III) species, as corroborated by the crystal structure of 5. In this compound, two amide-nitrogen and two phenolate-oxygen atoms of a fully deprotonated (L(3))(4-) anion build a slightly distorted square planar surrounding around the cobalt atom, the Co-N distances [1.858(3) and 1.861(3) A] being somewhat longer than the Co-O ones [1.798(3) and 1.801(3) A]. Magnetic and 1H NMR data at room temperature for 6-8 support the occurrence of an intermediate S = 1 low-lying state for the Co(III) center which is stabilized by the strong donating ability of the fully deprotonated bis-amidate ligands. In the case of the compound with the naphthalene derivative (9), the analytical and spectroscopic data suggest the occurrence of a low spin Co(II) complex. The weakening of the ligand field strength of the tetradentate bis-amidate ligand in the naphthalene derivative (5-6-5 ring-membered fused chelate) when compared to the situation in complexes 5-8 (5-5-5 ring-membered fused chelate) would account for this feature.     

Electrogenerated Fe(I) Porphyrins: Efficient Electrocatalysts for Reductive Dechlorination of DDT in N,N′‐Dimethylformamide

Two iron(I) porphyrins were electrogenerated and then utilized as catalysts for the reductive dechlorination of 1,1‐bis(4‐chlorophenyl)‐2,2,2‐trichloroethane (DDT) in N,N′‐dimethylformamide. No reaction is observed between DDT and the Fe(III) or Fe(II) forms of the porphyrin, but the electrogenerated Fe(I) porphyrin efficiently catalyzes the electroreduction of DDT to give (1,1‐bis(4‐chlorophenyl)‐2,2‐dichloroethane) DDD, (1,1‐bis(4‐chlorophenyl)‐2,2‐dichloroethylene) DDE and (1,1‐bis(4‐chlorophenyl)‐2‐dichloroethane) DDMU as determined by GC‐MS analysis. The reductive dechlorination was monitored by electrochemistry, controlled potential electrolysis and spectroelectrochemistry and a mechanism for the reaction involving the reduced porphyrins and DDT is proposed. Comparisons are also made between the catalytic properties of metalloporphyrins containing iron, cobalt and manganese central metal ions under the same solution conditions.     

荧光光谱法研究卟啉与金属离子配位反应机理初探

本文用荧光光谱法初步研究了卟啉与金属离子配位反应机理和部分催化剂的催化机理.实验发现,在一定条件下,卟啉以一种与其主要存在形式不同的变形体H₂P^*存在,根据H₂P^*的存在和产生的条件,对卟啉与金属离子配位反应的一般条件作出了较为满意的阐述.     

Androgynous porphyrins. Silver(II) quinoxalinoporphyrins act as both good electron donors and acceptors

The metal-centered and macrocycle-centered electron-transfer oxidations and reductions of silver(II) porphyrins were characterized in nonaqueous media by electrochemistry, UV-vis spectroelectrochemistry, EPR spectroscopy, and DFT calculations. The investigated compounds are {5,10,15,20-tetrakis(3,5-di-tert-butylphenyl)porphyrinato}silver(II), {5,10,15,20-tetrakis(3,5-di-tert-butylphenyl)quinoxalino[2,3-b']porphyrinato}silver(II), {5,10,15,20-tetrakis(3,5-di-tert-butylphenyl)bisquinoxalino[2,3-b':7,8-b']porphyrinato}silver(II), and {5,10,15,20-tetrakis(3,5-di-tert-butylphenyl)bisquinoxalino[2,3-b':12,13-b']porphyrinato}silver(II). The first one-electron oxidation and first one-electron reduction both occur at the metal center to produce stable compounds with Ag(III) or Ag(I) metal oxidation states, irrespective of the type of porphyrin ligand. The electrochemical HOMO-LUMO gap, determined by the difference in the first oxidation and first reduction potentials, decreases by introduction of quinoxaline groups fused to the Ag(II) porphyrin macrocycle. This provides a unique androgynous character to Ag(II) quinoxalinoporphyrins that enables them to act as both good electron donors and good electron acceptors, something not previously observed in other metalloporphyrin complexes. The second one-electron oxidation and second one-electron reduction of the compounds both occur at the porphyrin macrocycle to produce Ag(III) porphyrin pi-radical cations and Ag(I) porphyrin pi-radical anions, respectively. The macrocycle-centered oxidation potentials of each quinoxalinoporphyrin are shifted in a negative direction, while the macrocycle-centered reduction potentials are shifted in a positive direction as compared to the same electrode reactions of the porphyrin without the fused quinoxaline ring(s). Both potential shifts are due to a stabilization of the radical cations and radical anions by pi-extension of the porphyrin macrocycle after fusion of one or two quinoxaline moieties at the beta-pyrrolic positions of the macrocycle. Introduction of quinoxaline groups fused to the Ag(II) porphyrin macrocycle provides a unique androgynous character to Ag(II) quinoxalinoporphyrins that enables them to act as both good electron donors and good electron acceptors.     

Convenient scaffold for forming heteroporphyrin arrays in aqueous media

A new methodology for preparing heteroporphyrin arrays in aqueous solution has been presented. The present method is based on the extremely strong ability of heptakis(2,3,6-tri-O-methyl)-beta-cyclodextrin (TMe-beta-CD) to include 5,10,15,20-tetrakis(p-substituted-phenyl)porphyrins (Por) affording trans-type 1:2 complexes of the porphyrins and TMe-beta-CD. Two different Por-per-O-methylated beta-CD (per-Me-beta-CD) conjugates were synthesized. Conjugate 2 was prepared by an S(N)2 reaction of 5,10,15,20-tetrakis(p-hydroxyphenyl)porphyrin and per-O-methylated beta-cyclodextrin having one primary OTs group. Four per-Me-beta-CD moieties are attached to the meso positions of 2. Conjugate 3, synthesized from 5-(p-hydroxyphenyl)-10,15,20-tris(3,5-dicarboxyphenyl)porphyrin and monotosylated per-O-methylated beta-cyclodextrin, has one per-Me-beta-CD moiety at the periphery of the porphyrin. Conjugate 2 yields a stable 1:4 complex with the zinc complex of 5-phenyl-10,15,20-tris(3,5-dicarboxyphenyl)porphyrin (8) in the dissociated form. In this system, the energy transfer from photoexcited Zn-8 to free base 2 occurs with 85% efficiency. Conjugate 3 forms a very stable 1:1 complex with Zn-8 (K = (7.0 +/- 0.3) x 10(5) dm(3) mol(-1)) with an energy transfer efficiency (93%) larger than that obtained in the case of 2. The structure of the 3-Zn-8 complex, which can account for the efficient energy transfer, was deduced from (1)H NMR spectroscopy. Intramolecular fluorescence quenching of 2 and 3 by Fe(III)-8 also occurred through an electron-transfer process as the main quenching mechanism. The present method is a very simple and convenient means to construct various heteroporphyrin arrays in aqueous solution.     

Fast nitroxyl trapping by ferric porphyrins

Iron(II) porphyrin nitrosyl complexes are obtained in high yields from the reaction of iron(III) porphyrins with the nitroxyl donors sodium trioxodinitrate and toluensulfohydroxamic acid. The reaction was found to proceed both in organic solvents and in aqueous media from iron(III) (meso-tetraphenyl) porphyrinate ([FeIII(TPP)]+) and iron(III) meso-tetrakis (4-sulfonatophenyl) porphyrinate ([FeIII(TPPS)]3-) or iron(III) protoporphyrin IX, respectively. The kinetic rate constant for the reaction of ([FeIII(TPPS)]3-) with sodium trioxodinitrate (kon) was estimated to be 1.00 +/- 0.04 x 107 M-1 s-1. As well as resulting in a versatile method for obtaining ferrous nitrosyl porphyrins, the reaction points at ferric porphyrins as efficient nitroxyl traps and provides a tool to model nitroxyl reactivity toward hemeproteins.     

Synthesis of Vinylene-Co,N-Linked Multi(porphyrin)s by the Addition of Free-Base Porphyrins to a C(2)H(2) Complex of Cobalt(III) Porphyrin and Their Oxidative Rearrangement to Vinylene-N,N'-Linked Multi(porphyrin)s

The nucleophilic addition reaction of a pyrrole nitrogen of free-base porphyrins to a pi-complexed acetylene ligand in a cationic Co(III) porphyrin intermediate afforded good yields of vinylene-Co,N'-linked bis(porphyrin)s, (Por)Co(III)-CH=CH-(N-Por)H(2). N-substituted porphyrin free bases are N-vinylated regioselectively at the pyrrole adjacent to the original N-substituted pyrrole in this reaction. Tris- and tetrakis(porphyrin)s have been prepared by reacting a vinylene-N,N'-linked bis(meso-tetraarylporphyrin) with (OEP)Co(III)(H(2)O)(2)ClO(4) (OEP: octaethylporphyrin dianion) and acetylene. The tetrakis(porphyrin) proved to be a 1:1 mixture of C(i)()- and C(2)-symmetric regioisomers. These organometallic Co(III) complexes underwent facile oxidative migration of the Co-bound vinyl group to a porphyrin pyrrole nitrogen when treated with Fe(III) salts or HClO(4) to provide moderate to good yields of Co(II) vinylene-N,N'-linked multi(porphyrin) complexes. (Vinylene-N,N')bis(porphyrin) free bases with combinations of different porphyrins have been obtained by this procedure. The homobinuclear (2Co(II), 2Cu(II), and 2Zn(II)) and heterobinuclear (Co(II)Cu(II) and Co(II)Zn(II)) complexes have been prepared and characterized spectroscopically. The single-crystal X-ray analysis of (CH=CH-N,N')[(OEP)Co(II)Cl][(TPP)Zn(II)Cl] (TPP: meso-tetraphenylporphyrin dianion) showed a face-to-face structure with an average inter-ring separation of 4.39 ? (triclinic P&onemacr;; Z = 2; a = 14.806(4), b = 18.703(10), c = 13.796(3) ?, alpha = 97.69(3), beta = 99.57(2), gamma = 96.74(3) degrees ).