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1.
Polydentate nitrogen donor ligands have been prepared for use in biomimetic dinuclear copper complexes designed to model the enzyme, tyrosinase.  相似文献   

2.
Introduction   Affinity chromatography is of great interest in pharmaceutical industry as it is simple,fast and is of a high efficiency to purify proteins from a complicated mixture to homogenousones in a single step. The most common affinity ligands are monoclonal antibodies,smallmolecules such as biotin and those specific to the bio-function of the protein of interest,suchas substrates and inhibitors. Although m Ab is less limited by the bioactivity of proteins,itspreparation is a complex …  相似文献   

3.
功能性多吡啶配体的合成   总被引:13,自引:0,他引:13  
经过多步反应,合成了10个新的多吡啶配体,其中,有带强吸附性的基团(磷酸基、羧基),有对pH敏感及具有平面大共轭体系的联多吡啶配体及其中间体,用光谱鉴定了它们的结构.  相似文献   

4.
李瑛  吴德贤  朱槿  赵华明 《有机化学》1988,8(2):158-161
有机金属配合物涉及了许多重要的生命过程,配体和配合物的合成及性质研究都越来越受到人们的重视。磺酰胺类化合物,磺酰胺中氨基氢的酸性可与酚类化合物相比拟,对金属离子有较强的配位能力,并且比酚试剂不易氧化,还可改变磺酰胺的空间体积和亲脂性。本文报道一类新的磺酰胺型多齿配体的合成,并证明它们能与金属离子形成配合物。  相似文献   

5.
More and more metal complexes with terminal borylene ligands will be synthesized. Although these ligands in metal complexes must be stabilized either by integration of the boron atom into a polyhedral skeleton ( 1 ) or by B–N π interactions with a bulky amino group ( 2 ), the route to new complexes with terminal RB ligands (R=alkyl, aryl) is clearly indicated.  相似文献   

6.
The selectivity of macrocyclic ligands such as crown ethers and cryptands in binding metal and other cations in aqueous and nonaqueous solvents can be exploited to make ion separations. Cations are usually separated by direct interaction with the ligand. In addition, anions associated with the positively charged macrocyclic complexes can be separated in novel separations systems. We have incorporated macrocyclic ligands into high performance ion chromatography, liquid membranes, and solvent extraction separation systems involving coalescence extraction.  相似文献   

7.
超分子双膦配体是一类新兴起的基于非共价键作用构筑的双膦配体,近年来引起人们的重视.与传统的共价键连接的双膦配体相比,利用非共价相互作用的可逆性和选择性,超分子双膦配体具有合成简便,组合灵活,易于合成超分子配体库,并利用组合化学的方法对催化体系进行优化和筛选等优点.详细综述了近几年发展的基于氢键、配位键、主客体作用和静电作用等弱相互作用的超分子双膦配体,重点讨论了它们的构建方法以及在不对称催化反应中的应用,并对其发展前景进行了展望.  相似文献   

8.
不对称催化氢甲酰化中高效手性配体的进展   总被引:2,自引:0,他引:2  
比较系统地总结了应用于不对称催化氢甲酰化方面各类配体的合成、设计思路及性能,侧重于评述高效配体的最新进展.  相似文献   

9.
孔勇 《化学通报》2020,83(9):792-798
N-杂环卡宾(NHC)配体的优异催化性能引起了人们的广泛关注,已成功应用于多种烯烃聚合反应。本文主要介绍NHC及其在开环易位聚合、烯烃配位聚合和原子转移自由基聚合等反应中的应用。在此基础上,指出了今后NHC配体在聚合反应研究的发展方向。  相似文献   

10.
张占辉 《有机化学》2005,25(4):355-363
手性螺环配体的合成及其在不对称催化反应中的应用是不对称合成和催化研究中重要的研究领域之一, 一些手性螺环配体被合成出来并成功地应用于不对称催化反应中. 综述了近十年来手性螺环配体的合成及在不对称催化反应中的应用研究进展.  相似文献   

11.
宋庆宝  东宇 《有机化学》2007,27(1):66-71
综述了具有独特结构的二茂铁手性膦配体的合成及应用. 这类化合物在催化不对称合成反应中表现出了很高的活性.  相似文献   

12.
Recent developments in the synthesis of phosphazene-based ligands (preparation of polyfunctional coordination ligands such as pyridyloxy-, pyrazolyl-, phenanthroline-, porphyrine-, carboxyl-, fluorene-, 1,1'-bis-2-naphthol-, coumarin-, and oxazoline-containing cyclophosphazenes as well as phosphazenes containing crown ether and spirocyclic groups) are reviewed. Coordination behavior, complex formation properties, and certain peculiar features of these ligands are described. Special attention is paid to their applications in science and technology.  相似文献   

13.
Abstract

The anions of P,N-cyclic metaphosphimic acids (MPmn-, n = =3, 4…) interact with cations as conformationally labile multidentate ligands. They belong to the cyclophosphazane class and can be obtained from chloroderivatives (NPCl2)n associated with a related class of P,N-compounds (cyclophosphazenes. Besides halogens, a great variety of organic radicals can act as substituents in the cyclophospnazenes. An additional introduction of donating atoms or groups in these radicals results in new multidentate ligands. Like the MPmn- they demonstrate a cation binding ability. Thus P,N-cyclic ligands can contain endocyclic functional groups POO- which are inherent to common MPmn- or various exo-cyclic groups, e.g. -COO?, -PR2O?, -PROO?, -NR2etc., linked to the cycle via side chains. Furthermore, miscellaneous phosphazane-phosphazene structures as well as those with an additional heteroatom can be designed. We have obtained the first examples of P,N-cyclic chelantes of some structural types. These are bicycles based on MPmn- cross-linked by organic bridges. Such ligands can take a sandwich configuration. Neutral and acido-ligands of cyclo-pendante type involving groups -COO?, -PPh2O and >O as well as a ligand with endocyclic sulfur have been obtained too. Selective or universal chelantes, extragents, coloured ligands and other reagents can be synthesized depending on a ligand structure design, the nature of organic fragments linked to the cycle and the type of functional groups.  相似文献   

14.
亲和色谱仿生配基的筛选和设计   总被引:1,自引:0,他引:1  
任军  贾凌云 《分析化学》2005,33(9):1345-1349
利用选择性好、稳定性高、价格低廉的仿生配基作为亲和色谱的功能基团,实现对目的蛋白质的亲和分离,可以弥补常规的单克隆抗体和其他天然蛋白质配基在价格、稳定性方面的不足,从而拓展亲和色谱技术的应用范围。本文综述了亲和色谱仿生配基在筛选和设计方面的研究进展,重点介绍了组合方法和基于结构的仿生配基的设计及其应用。  相似文献   

15.
Much attention has been paid to new polydentate ligands usually formed by a central heteroaromatic ring conveniently linked to one or two arms bearing heteroatoms (these arms can be heterocycles). For ligands N?N?N, C?N?N, N?C?N, O?N?N, O?N?O and O?N?N?O …  相似文献   

16.
前手性酮的不对称氢转移反应(ATH)是获得手性醇的重要方法.近年来氨基酸及其衍生物在金属Ru,Rh,Ir催化酮的ATH中的应用引起人们关注.就氨基酸、氨基酸酰胺、氨基酸硫代酰胺、氨基酸羟胺酸、氨基酸酰肼、氨基醇及氨基酸羟基酰胺等为配体的金属络合物在ATH中的催化性能进行了综述.  相似文献   

17.
陈熙  邹敏 《化学通报》2023,86(6):742-747
金属-有机框架材料(Metal-Organic?Frameworks,简称MOFs)是由金属离子(簇)与有机桥接配体通过配位共价键或弱相互作用自组装形成的一类具有分子内孔隙的有机-无机杂化材料。羧酸类MOFs材料中金属中心和有机羧酸配体的可变性导致了其结构和功能的多样性,在气体的吸附与分离、荧光、传感、药物传输以及电催化等多个领域展现了独特的应用前景,并被认为是当今科学上最有前途的材料之一。对于有机配体的选择,从早期易坍塌的含氮杂环类配体过渡到了如今稳定性好的羧酸类配体,解决了不少以前出现的MOFs材料结构单一易坍塌问题。  相似文献   

18.
Rhodium-catalyzed hydroformylation of olefins is an important method for synthesizing aldehydes, and it is worth noting that regioselectivity and enantioselectivity of the product controlled by ligand are the most commonly used strategies. The modular synthesis of phosphite and phosphoramidite ligands have significant advantages of simple synthesis and high catalytic activity, which was why these ligands have been widely used in hydroformylation reactions. Herein, we focus on the synthesis methods and design ideas of such ligands, as well as their application effects in hydroformylation reactions. This review aims to provide a reference for the design and synthesis of ligands in hydroformylation subsequently.  相似文献   

19.
20.
Ligand design is becoming an increasingly important part of the synthetic activity in chemistry. This is of course because of the subtle control that ligands exert on the metal center to which they are coordinated. Ligands which contain significantly different chemical functionalities, such as hard and soft donors, are often called hybrid ligands and find increasing use in molecular chemistry. Although the interplay between electronic and steric properties has long been recognized as essential in determining the chemical or physical properties of a complex, predictions remain very difficult, not only because of the considerable diversity encountered within the Periodic Table-different metal centers will behave differently towards the same ligand and different ligands can completely modify the chemistry of a given metal-but also because of the small energy differences involved. New systems may-even through serendipity-allow the emergence of useful concepts that can gain general acceptance and help design molecular structures orientated towards a given property. The concept of ligand hemilability, which finds numerous illustrations with hybrid ligands, has gained increased acceptance and been found to be very useful in explaining the properties of metal complexes and in designing new systems for molecular activation, homogeneous catalysis, functional materials, or small-molecule sensing. In the field of homogeneous enantioselective catalysis, in which steric and/or electronic control of a metal-mediated process must occur in such a way that one stereoisomer is preferentially formed, ligands containing one or more chiral oxazoline units have been found to be very valuable for a wide range of metal-catalyzed reactions. The incorporation of oxazoline moieties in multifunctional ligands of increasing complexity makes such ligands good candidates to display hemilabile properties, which until recently, had not been documented in oxazoline chemistry. Herein, we briefly recall the definition and scope of hemilabile ligands, present the main classes of ligands containing one or more oxazoline moieties, with an emphasis on hybrid ligands, and finally explain why the combination of these two facets of ligand design appears particularly promising.  相似文献   

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