金属卟啉在新型材料领域的应用进展

作为新型材料其中一员,卟啉及金属卟啉在光电器件、医药和功能材料等领域具有重要的研究意义和广泛的应用前景。本文综述了近年来卟啉及金属卟啉化合物在新型材料方面的研究,重点介绍了金属卟啉化合物在电化学、分子自组装及催化等方面的应用新进展,并对其未来在新型材料领域的研究进行了展望。     

负载金属卟啉用于催化氧化反应的进展

文中记述了近年来固载金属卟啉应用于催化氧化研究反应的现状,包括金属卟啉以及载体的种类,认为固载金属卟啉模拟酶催化剂在催化氧化反应中将有更大的应用前景。     

Solid‐phase extraction of phenolic compounds with poly[metalloprotoporphyrin IX]

A highly insoluble metalloporphyrin polymeric material was used as sorbent for the solid‐phase extraction of phenolic compounds. Substantial quantities of phenols (40 to 60 mg/g polymer) were absorbed from aqueous solution comparing satisfactorily with other extraction methods. The polymeric phase presented similar K_SPE values for the hydrophobic compounds tested such as p‐chlorophenol, BPA, p‐nitrophenol, and a significant lower value for the more hydrophilic p‐aminophenol and cresol. Several metallic complexes of protoporphyrin IX (Co²⁺, Cu²⁺, Ni²⁺, Zn²⁺, and Fe³⁺) have been tested. The analytes were extracted with high recoveries at acid and neutral pH values, whereas at pH 10 low recoveries were obtained. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3038–3043, 2001     

金属卟啉催化氧化环己烷最新研究进展

系统综述了金属卟啉催化氧化环己烷的最新研究进展,包括以PhIO、PhI （OAc）₂、O₂、t-BuOOH、NaIO₄和H₂O₂为氧化剂的各种氧化体系。认为开发以O₂为氧化剂、高活性高选择性的非均相金属卟啉催化体系是今后金属卟啉催化氧化环己烷的主要方向,尤其是多金属中心的金属卟啉体系,将对O₂具有高活化性能和对环己基过氧化氢分解转化具有高催化活性的金属卟啉共价键连组合,构筑多金属中心的金属卟啉体系,促进环己烷催化氧化体系中底物转化率和产物选择性的提高。本综述不仅对开发高活性、高选择性的环己烷催化氧化体系,改进目前工业上环己烷催化氧化体系具有重要的参考价值,而且对其他烃类C-H键和C-C键高效催化氧化体系,甚至其他氧化体系的研究开发也具有重要的参考价值。     

可视嗅觉传感器阵列研究及图像分析

针对目前电子鼻系统普遍存在的检测范围窄、受环境湿度影响较大等缺点,本文依据金属卟啉配合物与有机气体反应会产生颜色变化的原理,研制了一种新型的气体敏感膜,设计了可视嗅觉传感器阵列的实验系统.系统通过分析敏感膜与不同的气体反应所呈现的颜色变化识别气体,具有完全不受外界水蒸气影响和检测精度高等特点.用该传感器敏感膜分别对环己胺、乙腈和四氢呋喃进行了试验,试验结果表明该传感器阵列能够正确地识别这三种有机物.     

金属卟啉仿生催化剂进展

细胞色素P-450是一种生物体内催化分子氧氧化内源底物的单加氧酶,其活性片段的核心结构是金属卟啉络合物。人工合成的金属卟啉络合物可作为细胞色素P-450的有效模拟物,应用于烯烃、直链烷烃、环烷烃、芳烃、芳烃侧链、及各种杂原子等多种底物的催化氧化。人工合成的金属卟啉络合物可分为：对称型金属卟啉、非对称型金属卟啉、μ-氧代双核金属卟啉、负载型金属卟啉4大类。现以金属卟啉络合物的结构为线索,论述了结构与催化活性及稳定性的内在联系,重点介绍了近几年国内外金属卟啉仿生催化剂的氧化应用研究进展,及仿生催化氧化的工业化发展前景。     

CoTPP-TBAB catalyzed tandem transformation of styrene carbonate from styrene in the presence of O2 and CO2

The direct synthesis cyclic carbonate from styrene, O₂ and CO₂ is of great academic attraction and industrial value in modern chemistry. The metalloporphyrin/tetrabutylammonium bromide was employed as binary catalyst for this reaction in the presence of O₂ and CO₂ by using methyl 2-cyclopentanone-carboxylate as co-catalysts. The effects of reaction parameters on catalytic performance were investigated systematically. Under the optimal reaction conditions, conversion of styrene (99%) and selectivity to cyclic carbonate (35%) were obtained. The possible mechanism of cascade reaction was proposed by using in-situ ultraviolet and infrared spectroscopy. The results show that the cobalt center is coordinated with the ring oxygen atom of methyl 2-oxocyclopentanecarboxylate to activate oxygen to form a peroxy active species, thereby forming a high-valent cobalt-oxygen intermediate, which passes oxygen atoms to styrene and generate epoxy styrene. Then, styrene oxide opened ring under the catalysis of tetrabutylammonium bromide, and finally formed cyclic carbonate through CO₂ insertion reaction and intramolecular ring-closing reaction.     

金属卟啉催化氧气选择氧化对甲基异丙苯绿色合成对甲基苯乙酮

以对甲基异丙苯为原料、无溶剂条件下,选取不同环外取代基和中心金属离子的金属卟啉作为催化剂,氧气为氧源,绿色氧化对甲基异丙苯合成对甲基苯乙酮。探讨了不同种类催化剂的催化活性、不同浓度的催化剂、反应温度和氧气压力对目标化合物的选择性和收率的影响。实验显示,在T(p-OCH_3)PPCo Cl作为催化剂、反应温度为110℃、压力为2.0 MPa时,对甲基异丙苯的转化率为43.4%,对甲基苯乙酮的选择性高达47.4%,收率为20.7%。     

Metal-Oxo Species in P450 Enzymes and Biomimetic Models. Oxo-Hydroxo Tautomerism with Water-Soluble Metalloporphyrins

Oxygenation reactions (hydroxylation, epoxidation, N- or S-oxide formation, etc.) catalyzed by cytochrome P450 enzymes and related biomimetic models involve an electrophilic oxidative species as the active species, namely a high-valent metal-oxo intermediate. Among the different methods to study the oxygenation reactions mediated by high-valent metal-oxo porphyrin complexes, the recent discovery of oxo-hydroxo tautomerism provides a useful tool to investigate the mechanism of O-atom transfer reactions in aqueous media.     

A [meso-tetrakis(4-sulfonatophenyl)porphyrinato]zinc(ii) complex as an oral therapeutic for the treatment of type 2 diabetic KKA(y) mice

We prepared and characterized [meso-tetrakis(4-sulfonatophenyl)porphyrinato]zinc(II) ([Zn(tpps)]), and investigated its in vitro insulin-mimetic activity and in vivo hypoglycemic effect in type 2 diabetic KKA(y) mice. The results were compared with those of previously proposed insulin-mimetic zinc(II) complexes and zinc sulfate (ZnSO(4)). The in vitro insulin-mimetic activity of [Zn(tpps)] was considerably better than that of bis(allixinato)zinc(II) ([Zn(alx)(2)]), bis(maltolato)zinc(II) ([Zn(mal)(2)]), bis(2-aminomethylpyridinato)zinc(II) ([Zn(2-ampy)(2)](2+)), and ZnSO(4). In particular, the order of in vitro insulin-mimetic activity of the complexes was determined to be: [Zn(tpps)]>[Zn(alx)(2)]>[Zn(mal)(2)]>[Zn(2-ampy)](2+)>ZnSO(4). [Zn(tpps)] normalized the hyperglycemia of KKA(y) mice within 21 days when administered orally at doses of 10-20 mg (0.15-0.31 mmol) Zn per kg body mass for 28 days. In addition, metabolic syndromes such as insulin resistance, the degree of renal disturbance, and the degree of liver disturbance were significantly improved in [Zn(tpps)]-treated KKA(y) mice relative to those administered with saline and ZnSO(4). The improvement in diabetes was validated by the results of oral glucose-tolerance tests and the decrease in the HbA(1c) level observed. In contrast, ZnSO(4) and the ligand H(2)tpps did not lower the elevated blood glucose level under the same experimental conditions. Based on these observations, [Zn(tpps)] is proposed to be the first orally active zinc(II)-porphyrin complex for the efficacious treatment of not only type 2 diabetes but also metabolic syndromes in animals.