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1.
聚类卟啉金属配合物*   总被引:1,自引:0,他引:1  
王荣民  赵明  何玉凤  郝二霞  申国瑞 《化学进展》2007,19(11):1783-1790
为模拟天然卟啉所具有的特殊生理活性,结构与性能各异的多种金属卟啉被合成并应用于许多领域。实际上,天然金属卟啉是在特定天然高分子-蛋白质营造的空穴中才能发挥其独特的性质,因此,类卟啉金属配合物的高分子化逐渐受到关注,并在载氧、催化、导电等领域取得重要成果。基于结合方式不同,高分子类卟啉金属配合物可分为高分子担载类卟啉金属配合物与聚类卟啉金属配合物。其中,后者以稳定的类卟啉环作为高分子链,不但使高分子骨架稳定,而且活性中心与类卟啉金属配合物之间有效间隔,同时活性中心相对密集,使其表现出较高的稳定性与活性。线形与平面型聚金属卟啉与金属酞菁表现出良好的导电性与催化活性;手性Salen席夫碱易于聚合得到线形或网状聚Salen希夫碱金属配合物,其表现出较强的催化活性、高ee值和可循环性。异双核聚类卟啉金属配合物也表现出较强的催化活化分子氧性能。  相似文献   

2.
A new polymeric ligand was synthesized by the reaction of bisphenol-A and formaldehyde in the basic medium, followed by condensation polymerization with barbituric acid in the acidic medium. Polymer metal complexes were prepared by reaction of this resin with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II). The polymeric resin and its metal polychelates were characterized by elemental analysis, FT-IR, 13C-NMR, and 1H-NMR spectra. The geometry of the polymer metal complexes was evaluated by electronic spectra (UV-Vis) and magnetic moment measurement. Thermal stabilities show an increased thermal stability of the metal polychelates compared to the ligand. The antibacterial activities of all the synthesized polymers were investigated against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli, showing good antibacterial activities against these bacteria. Cu(II) polychelate showed highest biocidal activity.  相似文献   

3.
Advances in metal incorporated resins are now an active field of research. To develop resin having better antimicrobial and thermal activity, a series of metal-chelated resins have been synthesized by the condensation of (4-aminobenzene-1,3-diyl)dimethanol with 2,6-diaminohexanoic acid in alkaline medium and then this polymeric ligand further reacts with transition metal ions forming various coordination polymers. (4-Aminobenzene-1,3-diyl)dimethanol was initially prepared by the reaction of aniline and formaldehyde in 1?:?2 molar ratio in alkaline medium. The analytical data reveal that the polymer metal complexes of Mn(II), Co(II), and Ni(II) are coordinated with two water molecules, which are further supported by FTIR spectra and TGA data. Comparative analyses of the polymer metal complexes in thermal curves show better thermal stability than the polymeric ligand. Since these resins are relatively stable at high temperatures, they can be used for medical and biomaterial applications requiring thermal sterilization, solvent-resist coating materials because of their insoluble nature, and antifouling coating materials owing to antimicrobial activity in ?elds such as life-saving medical devices and the bottoms of ships.  相似文献   

4.
以水杨醛与苯基羟胺缩合制备的酚硝酮为配体制备了Zr的配合物,采用IR、NMR、元素分析、质谱等表征手段对酚硝酮配体以及催化剂的结构进行了表征.研究了以酚硝酮为配体的Zr的配合物与MAO组成的催化体系催化乙烯聚合的行为.研究结果表明,该催化剂乙烯均聚活性较高且具有较好的耐温性,乙烯均聚的活性大于106g/(molZr·h),催化剂的活性随着温度的升高有较大幅度的提高且在100℃条件下活性仍无明显衰减.另外,采用凝胶渗透色谱以及示差扫描量热法对制备的一系列聚乙烯的分子量、分子量分布以及热性能进行了表征,催化得到的聚乙烯分子量可达到105,熔点在132℃左右.  相似文献   

5.
表面增强拉曼散射(SERS)自1974年被Fleischmann等[1]发现以来,日益受到人们的重视.通过SERS谱图分析,可以获得物质结构及其与基体作用的信息.由于SERS可使拉曼信号增强105~106[2],并且在某些情况下银胶还能使表面吸附质的荧光猝灭[3,4], SERS常用来检测一些普通拉曼光谱难以检测的样品和考察界面络合物的形成.  相似文献   

6.
Electrochemical dissolution of sacrificial Pd anode was used to synthesize novel polynuclear PdII complexes with ligands based on polyamic acids containing in the main chain biquinolyl groups capable of coordination to the metal ions. The synthesized polymeric complexes exhibit high catalytic activity in the Suzuki reaction. The reaction can be run under mild conditions, at 40 °C and with a sufficiently high product yield at a catalyst concentration of 0.05 mol.% (with respect to the starting aryl halide). The polymeric ligand allows immobilization of the catalyst on the graphite fabric with high specific surface area that enhances the catalyst turnover number and promotes its recycling.  相似文献   

7.
A Ni(II) coordination polymer [C42H42K2N4Ni4O27] has been synthesized under open-air mild reaction conditions and characterized by physicochemical and spectroscopic methods. The X-ray crystal structure of the complex has been obtained. The crystallographic data revealed that each metal center is in a distorted octahedral geometry where the ligand coordinates to the metal centers by a nitrogen from the imine group, an oxygen from the carboxylic acid and a phenoxide group as an endogenous bridge to the metal centers. The coordination sphere is completed by an acetate, coordinated as an exogenous bridging ligand to both nickel centers, plus one terminal water ligand on each nickel. The polymeric structure is an infinite chain involving the binuclear nickel structure and K+ ions. Carbon paste electrodes modified with the Ni(II) coordination polymer were prepared, and the electrochemical behavior and electrocatalytic activity toward H2O2 reduction were investigated. The electrochemical results suggest that this Ni(II) coordination polymer has good catalytic activity with respect to H2O2 reduction.  相似文献   

8.
新的聚苯乙烯负载锌化合物:高效苯酚氧化催化剂(英文)   总被引:1,自引:0,他引:1  
The novel recyclable free –ONNO– tetradentate Schiff base ligand N,N′‐bis(2‐hydroxy‐3‐ methox‐ybenzaldehyde)4‐methylbenzene‐1,2‐diamine (3‐MOBdMBn) was synthesized. Complexation of this ligand with zinc(3‐MOBdMBn‐Zn) was performed, and the catalytic activity of the complex was evaluated. The polymer‐supported analog of this complex(P‐3‐MOBdMBn‐Zn) was synthesized, and its catalytic activity was studied. These free and polymer‐anchored zinc complexes were prepared by the reactions of metal solutions with one molar equivalent of unsupported 3‐MOBdMBn or P‐3‐MOBdMBn in methanol under nitrogen. The catalytic activity of 3‐MOBdMBn‐Zn and P‐3‐MOBdMBn‐Zn was evaluated in phenol oxidation. The activity of P‐3‐MOBdMBn‐Zn was signif‐icantly affected by the polymer support, and the rate of phenol conversion was around 50% for polystyrene‐supported 3‐MOBdMBn. The experimental results indicated that the reaction rate was affected by the polymer support, and the rate of phenol conversion was 1.64 μmol/(L·s) in the presence of polystyrene‐supported 3‐MOBdMBn.  相似文献   

9.
郭洪辰  秦玉升  王献红  王佛松 《应用化学》2019,36(10):1118-1127
铝卟啉是一类土壤环境友好的金属卟啉,尽管早在1978年Inoue就已经发现它可以催化CO2和环氧丙烷的共聚反应,但是该催化体系一直面临催化活性低、聚合物相对分子质量低等难题。 本文通过改变铝卟啉催化剂配体中苯环上取代基的种类和位置,制备出中心金属电子环境差异化的铝卟啉,并以双三苯基膦氯化铵(PPNCl)为助催化剂,探讨其对CO2与环氧丙烷的共聚反应的催化行为。 结果表明,当铝卟啉中苯环上2,4位同时被Cl-取代后,在90 ℃和3 MPa压力下,转化频率(TOF)达到2672 h-1。 当利用离去能力较强的对甲苯磺酸基团(OTs-)作为铝卟啉的轴向配体,可以合成出数均相对分子质量达1.84×105的脂肪族聚碳酸酯。  相似文献   

10.
水溶性卟啉催化氧化1,5-萘二酚   总被引:1,自引:0,他引:1  
合成并表征了系列水溶性卟啉配体[H2TPPS: 5,10,15,20-四-(4-磺酸基苯基)-21H,23H-卟啉, H2TMPyP: 5,10,15,20-四(4-吡啶基)-21H,23H-卟啉, H2TCPP: 5,10,15,20-四-(4-羧基苯基)-21H,23H-卟啉]及相应的铁、锌及钴配合物. 将水溶性卟啉作为光敏剂, 用于1,5-萘二酚的光催化反应, 产物为5-羟基-1,4萘醌. 利用UV-Vis方法对卟啉催化1,5-萘二酚的反应过程进行了监测, 探索了水相和水/二氯甲烷双相催化体系, 确定了较为理想的反应条件. 探讨了不同取代基和不同金属离子对卟啉催化性能的影响, 初步讨论了催化机理. 结果表明, 具有磺酸根阴离子取代基的水溶性卟啉具有最好的催化活性; 卟啉的催化活性与其在反应体系中的稳定性密切相关; 铁卟啉在反应初期呈现很高的催化活性, 但在光照条件下容易发生光解而导致催化活性的降低; 无金属的磺酸卟啉在催化体系中的催化活性和稳定性最好.  相似文献   

11.
Decomposition of hydrogen peroxide was examined was examined by using Cu(II)–poly(vinyl alcohol) (PVA) as catalyst. The rates of decomposition were measured. Electronic spectra and infrared spectra of Cu(II)–PVA complex systems were determined at various stages of decomposition. Effect of addition of various amines to the Cu(II)–PVA system on catalytic action was considered. The relation between the initial rate and the initial concentration of hydrogen peroxide varied in accordance with the rate expression of Michaelis-Menten type. Cu(II)–PVA complex was found to have a large catalytic activity, while the polymeric PVA ligand and copper(II) ion exhibited less activity than Cu(II)–PVA complex. For hydrogen peroxide decomposition, Cu(II)–PVA complex showed catalytic activity when a stable complex of planar structure formed, while many other polymer complexes reported by other authors showed the catalytic activity when they were in unstable complex forms. An amine substituent has a critical influence on the rate of hydrogen peroxide decomposition. The mechanism in the first step of reaction for hydrogen peroxide decomposition is discussed.  相似文献   

12.
N,N′-bis(salicylidene)thiosemicarbazide Schiff base has been synthesized by the reaction of thiosemicarbazide with salicylaldehyde and then reacted with formaldehyde to generate phenolic groups, resulting in the formation of Schiff-base monomeric ligand. It was further incorporated with transition metals, Mn+2, Co+2, Ni+2, Cu+2, and Zn+2, to form Schiff-base metal complex, which was then polymerized with toluene 2,4-diisocyanate to form metal-chelated polyurethanes. Monomeric ligand, its metal complexes, and its metal polychelates were characterized and compared by elemental analysis, FT-IR, 1H NMR, thermal, and biocidal activities to evaluate the enhancement in physical and chemical properties on coordination with metal and on polymerization. SEM images of ligand and polymer metal complexes showed changes in surface morphology, while electronic spectra of polymer metal complexes were used to predict the geometry. Antimicrobial activities were determined by using agar-diffusion method with Staphylococcus aureus, Escherichia coli, Bacillus subtilis (bacteria), Aspergillus niger, Candida albicans, and Aspergillus flavus (yeast). The polymeric ligand had varied antibacterial and antifungal activities, enhanced after chelation and polymerization. Comparative results show that coordination of metal to the ligand enhances its physical and chemical properties which were meliorated on polymerization.  相似文献   

13.
诱捕在沸石超笼内的金属卟啉的催化性能   总被引:8,自引:0,他引:8  
诱捕在沸石超笼内的金属卟啉的催化性能*王杏乔高爽曹昌盛于连香曹锡章(吉林大学化学系,长春130023)关键词诱捕的金属卟啉,分子筛,苯乙烯,对甲酚,氧化众所周知,金属卟啉是一种共轭的大环化合物,这种化合物具有特殊的性能,尤其在氧化-还原反应中的催化性...  相似文献   

14.
本文研究了由过渡金属氯化物(MnCl_2、FeCl_2、CoCl_2、CuCl)与2,2′-二吡啶原位形成的配合物,在环己烯氧化反应中的催化性能以及配体性质对所形成的配合物催化性能的影响.结果表明,多种过渡金属氯化物可与2,2′-二吡啶原位形成有催化活性的配合物,其催化活性与金属离子性质、形成配合物能力以及配体性质有关.  相似文献   

15.
Novel polymer metal complexes were prepared by the condensation polymerization of a polymeric ligand with transition metal ions of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The polymeric ligand was prepared by the addition polymerization of urea with toluene 2,4‐diisocyanate in 1:1 molar ratio. The polymeric ligand and its polymer metal complexes were characterized by elemental analysis, Fourier transform infrared spectroscopy, 13C‐NMR, and1H‐NMR (nuclear magnetic resonance). The geometry was determined by electronic spectra and magnetic moment measurement. Thermogravimetric analysis (TGA) was utilized to find out the degradation process of the polyurea ligand and the polymer metal complexes. The TGA data revealed that all the metal‐containing polyureas are much more thermally stable than the corresponding polyurea ligand. The surface morphology of the polyurea ligand and cobalt(II)‐containing polyureas was determined by scanning electron micrographs. The antibacterial and antifungal activities of all the synthesized polymers were investigated against Staphylococcus aureus, Escherichia coli, and Bacillus subtilis (bacteria) and Aspergillus niger, Candida albicans, and Aspergillus flavus (fungi). These compounds show remarkably good biocidal activities, which were enhanced after complexation with the metal. Batch adsorption studies of the ligand were carried out for malachite green dye, and the polyurea ligand was found to be a good adsorbent for this dye. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

16.
本文研究了由过渡金属氯化物(MnCl2、FeCl2、CoCl2、CuCl)与2,2′-二吡啶原位形成的配合物,在环己烯氧化反应中的催化性能以及配体性质对所形成的配合物催化性能的影响.结果表明,多种过渡金属氯化物可与2,2′-二吡啶原位形成有催化活性的配合物,其催化活性与金属离子性质、形成配合物能力以及配体性质有关.  相似文献   

17.
几种新的聚合物冠醚的合成及其络合与催化性能   总被引:4,自引:0,他引:4  
由一、二、三和四缩乙二醇双钠盐与带有活泼卤原子的聚β-氯乙基缩水甘油醚进行环化反应,制备了四种新的聚合物冠醚(Ⅰ、Ⅱ、Ⅲ、Ⅳ)。络合容量测定结果表明,它们对K~+、Na~+均有较好的络合能力。在催化Wolff-Kishner(二苯甲酮腙还原为二苯甲烷)和正溴辛烷的碘代反应中,它们是有效的相转移催化剂。其中以Ⅱ最好,它的催化活性与小分子冠醚18-C-16和DB18-C-6相似,且易于回收,重复使用。  相似文献   

18.
合成了5,10,15,20-四(对-十四酰亚胺基苯基)卟啉配体(TMPPH2)及其锰、锌金属配合物(TMPPMnCl, TMPPZn), 并通过紫外-可见光谱、红外光谱、核磁共振氢谱、元素分析等技术对化合物的结构加以确认, 研究了配体和配合物的拉曼光谱、光电子能谱和荧光光谱的变化及电化学性质. 结果表明, 配体和配合物的紫外光谱、红外光谱、拉曼光谱、荧光光谱及光电子能谱都有很大区别, 锰配合物的循环伏安曲线与配体和锌配合物不同, 除了卟啉环发生氧化还原外, 还发生了金属离子的氧化还原反应.  相似文献   

19.
高分子卟啉及其金属配合物的研究进展   总被引:1,自引:0,他引:1  
高分子金属卟啉在载氧、导电及催化氧化性能方面日益受到重视,高分子金属卟啉有多种连接方式,如金属卟啉以配位键或共价键担载于高分子,金属卟啉轴向聚合及卟啉平面聚合等。本文综述了近10年来高分子卟啉及其金属配合物在合成和性能方面的最新研究成果。  相似文献   

20.
The polymeric ligand (BFP) was synthesized by condensation of bisphenol-A, formaldehyde, and piperazine in alkaline medium at 70–80°C. The polymer–metal complexes were synthesized by the reaction of BFP with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) acetates in 1?:?0.5 (ligand?:?metal) molar ratio. All the synthesized polymers were characterized by elemental, spectral (infrared, 1H-NMR, and UV-Vis), magnetic moment measurements, and thermal (TGA) analysis. The ligand-field and nephelauxetic parameters have been determined from UV-Vis spectra using ligand-field theory. Elemental analyses indicate the association of water with metal for Mn(II), Co(II), and Ni(II), which is also supported by TGA. The antimicrobial activities of the synthesized polymers were studied by agar well diffusion methods against Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, and Shigella boydii. The antimicrobial activity and thermal stability of Cu(II)–polymer were higher than the other polymer–metal complexes due to the higher stability constant of Cu(II).  相似文献   

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