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1.
The rational design and synthesis of metal-directed supramolecular framework compounds have received much attention in coordination chemistry because of their potential applications in catalysis, molecular selection, nonlinear optics, ion exchange, and microelectronics. Many high-dimensional coordination complexes have been designed and prepared through molecular self-assembly processes. The open metal organic framework can be produced via two kinds of interactions, i. e. , coordinate covalent bonds and weaker intermolecular forces. For this reason, the most efficient means to synthesize these compounds is to establish possible connections among different units.  相似文献   

2.
Biological function arises by the assembly of individual biomolecular modules into large aggregations or highly complex architectures. A similar strategy is adopted in supramolecular chemistry to assemble complex and highly ordered structures with advanced functions from simple components. Here we report a series of diamond‐like supramolecular frameworks featuring mesoporous cavities, which are assembled from metal‐imidazolate coordination cages and various anions. Small components (metal ions, amines, aldehydes, and anions) are assembled into the hierarchical complex structures through multiple interactions including covalent bonds, dative bonds, and weak C? H???X (X=O, F, and π) hydrogen bonds. The mesoporous cavities are large enough to trap organic dye molecules, coordination cages, and vitamin B12. The study is expected to inspire new types of crystalline supramolecular framework materials based on coordination motifs and inorganic ions.  相似文献   

3.
The design of molecular containers capable of selectively binding specific guest molecules presents an interesting synthetic challenge in supramolecular chemistry. Here, we report the synthesis and structure of a coordination cage assembled from Cu3I4 clusters and tripodal cationic N-donor ligands. Owing to the localized permanent charges in the ligand core the cage binds iodide anions in specific regions within the cage through ionic interactions. This allows the selective binding of bromomethanes as secondary guest species within the cage promoted by halogen bonding, which was confirmed by single-crystal X-ray diffraction.  相似文献   

4.
Mechanochemical reactions effected by milling or grinding are an attractive means to conduct chemical reactions dependent on molecular recognition and to systematically explore different modes of molecular self-assembly. The natural relationship between milling mechanochemistry and supramolecular chemistry arises primarily from the ability to avoid bulk solvent, which simultaneously avoids limitations of solution-based chemistry, such as solubility, solvent complexation, or solvolysis, and makes the resulting process highly environmentally friendly. This tutorial review highlights the use of mechanochemistry for the synthesis of supramolecular targets in the solid state, such as molecular hydrogen- or halogen-bonded complexes, molecular and supramolecular cages, open frameworks and interlocked architectures. It is also demonstrated that the molecular self-assembly phenomena that are well-established in solution chemistry, such as reversible binding through covalent or non-covalent bonds, thermodynamic equilibration and structure templating, are also accessible in milling mechanochemistry through recently developed highly efficient methodologies such as liquid-assisted grinding (LAG) or ion- and liquid-assisted grinding (ILAG). Also highlighted are the new opportunities arising from the marriage of concepts of supramolecular and mechanochemical synthesis, including organocatalysis, deracemisation and discovery of new molecular recognition motifs.  相似文献   

5.
超分子化学作为"广义上的配位化学",是一个充满活力的领域.基于配位自组装,设计合成具有不同拓扑结构和功能特性的超分子配合物是超分子化学的研究重点.基于稀土元素构筑的超分子配合物不仅丰富了配位超分子体系,也是制备功能性配合物的核心内容.主要从拓扑结构调控、结构修饰和功能特性等方面综述了螺旋、格子、环状和笼状等稀土超分子配...  相似文献   

6.
Inspired by the high efficiency and specificity of enzymes in living systems, the development of artificial catalysts intrinsic to the key features of enzyme has emerged as an active field. Recent advances in supramolecular chemistry have shown that supramolecular coordination cages, built from non-covalent coordination bonds, offer a diverse platform for enzyme mimics. Their inherent confined cavity, analogous to the binding pocket of an enzyme, and the facile tunability of building blocks are essential for substrate recognition, transition-state stabilization, and product release. In particular, the combination of chirality with supramolecular coordination cages will undoubtedly create an asymmetric microenvironment for promoting enantioselective transformation, thus providing not only a way to make synthetically useful asymmetric catalysts, but also a model to gain a better understanding for the fundamental principles of enzymatic catalysis in a chiral environment. The focus here is on recent progress of supramolecular coordination cages for asymmetric catalysis, and based on how supramolecular coordination cages function as reaction vessels, three approaches have been demonstrated. The aim of this review is to offer researchers general guidance and insight into the rational design of sophisticated cage containers for asymmetric catalysis.  相似文献   

7.
The covalent synthesis of nanosized cage compounds is easily performed in high yields using "click chemistry" methodology through the Cu(I)-catalyzed ligation of adequate polyalkyne and polyazide derivatives using (EtO)3P x CuI as catalyst.  相似文献   

8.
This report summarizes gold and silver chemistry with C-functionalized carborane ligands and also organometallic complexes with Au-Ccarboranyl σ bonds. The presence of different fragments bonded to the carbon atoms leads to ligands with different coordination preferences. Furthermore, through the partial degradation of the carborane cage the ligand charge can be modified and thus, anionic ligands are afforded. Consequently, for the synthesis of metal complexes, neutral and anionic ligands are available. These two aspects have been used to synthesise and stabilise a wide diversity of gold and silver coordination compounds. The use of carborane fragments as building blocks leads in some cases to unusual structures, clusters, rod like complexes and also to interesting properties like luminescent emissions.  相似文献   

9.
Dynamic covalent chemistry relates to chemical reactions carried out reversibly under conditions of equilibrium control. The reversible nature of the reactions introduces the prospects of "error checking" and "proof-reading" into synthetic processes where dynamic covalent chemistry operates. Since the formation of products occurs under thermodynamic control, product distributions depend only on the relative stabilities of the final products. In kinetically controlled reactions, however, it is the free energy differences between the transition states leading to the products that determines their relative proportions. Supramolecular chemistry has had a huge impact on synthesis at two levels: one is noncovalent synthesis, or strict self-assembly, and the other is supramolecular assistance to molecular synthesis, also referred to as self-assembly followed by covalent modification. Noncovalent synthesis has given us access to finite supermolecules and infinite supramolecular arrays. Supramolecular assistance to covalent synthesis has been exploited in the construction of more-complex systems, such as interlocked molecular compounds (for example, catenanes and rotaxanes) as well as container molecules (molecular capsules). The appealing prospect of also synthesizing these types of compounds with complex molecular architectures using reversible covalent bond forming chemistry has led to the development of dynamic covalent chemistry. Historically, dynamic covalent chemistry has played a central role in the development of conformational analysis by opening up the possibility to be able to equilibrate configurational isomers, sometimes with base (for example, esters) and sometimes with acid (for example, acetals). These stereochemical "balancing acts" revealed another major advantage that dynamic covalent chemistry offers the chemist, which is not so easily accessible in the kinetically controlled regime: the ability to re-adjust the product distribution of a reaction, even once the initial products have been formed, by changing the reaction's environment (for example, concentration, temperature, presence or absence of a template). This highly transparent, yet tremendously subtle, characteristic of dynamic covalent chemistry has led to key discoveries in polymer chemistry. In this review, some recent examples where dynamic covalent chemistry has been demonstrated are shown to emphasise the basic concepts of this area of science.  相似文献   

10.
Coordination Polymers from Metal Tripyrrins This Research Report summarizes recent advances in the coordination chemistry of tripyrrins and related ligands with a special emphasis on the structural chemistry of coordination polymers with such ligands. The tripyrrin ligand is unique in supporting the formation of 1D‐ and 3D supramolecular structures from pentacoordinate transition metal ions due to an effective blockage of their sixths coordination site. Linear coordination polymers have been observed with a multitude of bidentate and tridentate bridging ligands like trifluoroacetate, azide, thio‐ and selenocyanate, and higher order pseudohalides. Homo‐ and heterodimetallic species have been obtained by the use of cyanometallates and could be characterized structurally in two cases. Besides the covalent coordination bonds several secondary interactions like hydrogen bonding and π‐stacking were found to support these coordination polymers and are demonstrated to allow the preparation of species with functionalized inner surfaces.  相似文献   

11.
The imine bond--formed by the reversible condensation of an amine and an aldehyde--and its applications as a dynamic covalent bond in the template-directed synthesis of molecular compounds, will be the focus of this tutorial review. Template-directed synthesis--or expressed another way, supramolecular assistance to covalent synthesis--relies on the use of reversible noncovalent bonding interactions between molecular building blocks in order to preorganise them into a certain relative geometry as a prelude to covalent bond formation to afford the thermodynamically preferred product. The use of this so-called dynamic covalent chemistry (DCC) in templated reactions allows for an additional amount of reversibility, further eliminating potential kinetic products by allowing the covalent bonds that are formed during the template-directed reaction to be 'proofread for errors', thus making it possible for the reaction to search out its thermodynamic minimum. The marriage of template-directed synthesis with DCC has allowed chemists to construct an increasingly complex collection of compounds from relatively simple precursors. This new paradigm in organic synthesis requires that each individual piece in the molecular self-assembly process is preprogrammed so that the multiple recognition events expressed between the pieces are optimised in a highly cooperative manner in the desired product. It offers an extremely simple way of making complex mechanically interlocked compounds--e.g., catenanes, rotaxanes, suitanes, Borromean rings and Solomon knots--from relatively simple precursors.  相似文献   

12.
Three hybrid compounds have been synthesized through hydrothermal reactions of UO(2)(NO(3))(2)·6H(2)O with 4-halobenzoic acid (X = Cl, Br, I). The formation of these compounds utilizes a composite synthesis methodology that explicitly employs aspects of both coordination chemistry and supramolecular chemistry (namely halogen···halogen interactions).  相似文献   

13.
The tandem Claisen rearrangement is a simple but highly efficient reaction to synthesize useful building blocks for supramolecular chemistry. It provides in one step two new C-C bonds in very high yield. The scope and limits of this reaction will be discussed in this review and it will be shown, how macrocyclic compounds as well as rotaxanes or helicates can be formed by use of butenylidene bridged aromatic compounds obtained after the rearrangement reaction. Special aspects will cover the search for new receptors and sensors or for energy transfer properties. The contents of this tutorial review are within the field of preparative organic synthesis but in addition cover aspects of inorganic and supramolecular chemistry.  相似文献   

14.
Supramolecular coordination compounds bear exceptional advantages over their organic counterparts. They are available in one-pot reactions and in high yields and display physical properties that are generally inaccessible with organic species. Moreover, their weak, reversible, noncovalent bonding interactions facilitate error checking and self-correction. This Review emphasizes the achievements in supramolecular coordination chemistry initiated by serendipity and their materialization based on rational design. The recognition of similarities in the synthesis of different supramolecular assemblies allows prediction of potential results in related cases. Supramolecular synthesis obeys guidelines comparable to the "lead sheet" used by small jazz ensembles for improvisation and therefore more often leads to unpredicted results. The combination of detailed symmetry considerations with the basic rules of coordination chemistry has only recently allowed for the design of rational strategies for the construction of a variety of nanosized systems with specified size and shape.  相似文献   

15.
Russian Journal of Organic Chemistry - A promising area of modern coordination and supramolecular chemistry is the synthesis of biologically active compounds of germanium and creation of effective...  相似文献   

16.
Although the principle of template synthesis has been known since the sixties, surprising discoveries and new applications in the field of supramolecular chemistry over the last decade have provoked a boom in the subject. The synthesis of supramolecular species has been made much more efficient, or even in some cases possible, by the introduction of template ions or molecules. It is not just metal ions that can act as templates. Neutral molecules, electrostatic interactions, and hydrogen bonds also support the formation of binary and tertiary complexes. Energetically favorable conformations then lead to the formation of a specific desired product in high yield. In addition to the discussion of metal ions and neutral molecules as templates, covalent, positive, and negative templates are differentiated. Kinetic and thermodynamic aspects will also be considered in this review, together with the influence of templates on the phenomenon of self-organization. Further developments and applications include the synthesis of oligonucleotides, peptide blocks capable of forming secondary structure, and template polymers. Template synthesis of defined molecular cavities ultimately leads to “inclusion chemistry on a nanometer scale.”  相似文献   

17.
Artificial molecular architecture from a large number of subcomponents (>50) via self-assembly remains a formidable challenge for chemists. Reaction of 38 components [14 Ni(2+) and 24 N-methyl-1-(4-imidazolyl)methanimine] under solvothermal conditions reproducibly leads to the formation of a high-symmetry coordination cage. This polyhedral cage can also be obtained in high yield by self-assembly of 62 commercially available subcomponents (24 methylamine, 24 4-formylimidazole, and 14 Ni(2+)) under mild conditions involving synchronized formation of both dynamic covalent bonds and coordination bonds. Guest molecules (e.g., water, methylamine, and methanol) are randomly imprisoned in the cage.  相似文献   

18.
The synthesis and chemistry of polycyclic of cage compounds have attracted considerable attention in recent years. The vast majority of the work reported in this area has dealt with carbocylic cage compounds. On the other hand, the synthesis and chemistry of heterocyclic cage compounds have received less attention. Recently, we envisioned that studies on the synthesis and chemistry of heterocyclic cage compounds can greatly expand the scopes and utilities of cage compounds.1 As part of a program that involves the synthesis, chemistry, and application of heterocyclic cage compounds, we report here the synthesis of new thia-oxa-cage compounds and the chemical nature of these thia-cages.  相似文献   

19.
Functional molecules require a high degree of complexity which is difficult to achieve by covalent synthesis. This article discusses supramolecular approaches to the creation of larger architectures through noncovalent bonds, self-assembly, and template strategies. It highlights selected examples for the structural and conformational control of function and attempts to identify difficulties and challenges which may arise in future.  相似文献   

20.
三唑类超分子化学与药物研究新进展   总被引:1,自引:0,他引:1  
三唑环为含有三个氮原子的五元杂环, 唑环具有芳香性和丰富的电子, 易接受质子和络合金属离子, 因而三唑类化合物易通过配位键、氢键、离子-偶极、阳离子-?、?-?堆积、疏水效应以及范德华力等非共价键力形成超分子聚集体, 表现出许多特殊的性能及生物活性, 具有广泛的潜在应用如作为离子受体、材料、医药等. 近些年来, 相关三唑类超分子化学与医药的研究非常活跃, 发展特别迅速, 已成为十分活跃的热点研究领域. 本文结合自己的工作, 参考国内外近五年文献, 首次系统综述了三唑类化合物作为阳离子和阴离子受体以及三唑类超分子作为发光与磁性材料、医药在抗菌、抗真菌、抗癌等方面的研究与开发近况. 希望本综述对三唑类超分子化学与药物的进一步研发有所启迪.  相似文献   

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