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1.
Dynamic covalent iminofluorene-based oligomers and polymers have been generated. They undergo constitutional recomposition under the effect of two parameters, acidity and ZnII metal ions. As a result, marked changes in physical properties take place. The results illustrate the response of such a dynamic system to chemical effectors (H+ nd ZnII), thus demonstrating the adaptive behavior of the system under the pressure of external factors. They also point to the possibility of modulating optical properties (UV-visible absorption and fluorescence) by constitutional recomposition in response to a specific trigger. Such features allow the development of dynamic materials, the functional properties of which may respond to external stimuli.  相似文献   

2.
Concepts and strategies offered by constitutional dynamic chemistry (CDC) hold great promise for designing molecular computing systems adaptive to external environments. Despite demonstrable success in storing and processing chemical information using CDC, further employment of such constitutional dynamic networks (CDNs) for processing more complex digital information has not been realized yet. Herein, we introduced a supramolecular CDN based on the aggregation of cyanine MTC (Agg-CDN), which is composed of four reversibly interconvertible constituents, i.e. monomers, dimers, J-aggregates, and H-aggregates. We demonstrated that the equilibrated Agg-CDN is reconfigurable through constituent exchange in response to well-defined chemical inputs. More importantly, the equilibrated states of the Agg-CDN are spectroscopically distinguishable because of the unique optical properties of MTC. We further tuned the Agg-CDN to at least nine unique states for transforming the chemical inputs into digital outputs, and successfully employed it for encoding and encrypting complex digital information, such as multi-pixel images.

We constructed a supramolecular cyanine MTC aggregation-based constitutional dynamic network, which can transform the chemical information into image information reversibly.  相似文献   

3.
We describe the field of supramolecular chemistry as a consequence of the progress of chemistry from its premises to recent achievements. Supramolecular chemistry has been claimed to be an emergent field of research taking its roots in chemistry. According to the definitions of emergences related to hierarchy or more recently to scope, supramolecular chemistry is shown to have bottom-up or top-down emergences. The bottom-up emergence, directly related to hierarchy by definition, opens up the world of nanochemistry and nanomaterials while the top-down one, attributable to scope due to the implication of supramolecular chemistry in other fields of research, open the world of supramolecular biochemistry. Both emergences lead supramolecular chemistry to become a supramolecular science. Combining supramolecular chemistry with biology opens new direction in the study of life and it origin.  相似文献   

4.
Schmittel M  Saha ML  Fan J 《Organic letters》2011,13(15):3916-3919
By exploiting the supramolecular assistance of a sterically encumbered phenanthroline-Cu(+) motif, we report on the self-assembly of a trigonal nanoprism, its post-self-assembly functionalization, and transformation into a cage-like 3D framework with distinct compartments.  相似文献   

5.
The synthesis and properties of organophosphorus π-conjugated chromophores incorporating metallic ions are described. Their optical and electrochemical properties depend on the metal centre linked to the organophosphorus atom. Moreover, the introduction of metallic ions induces a control of the supramolecular organization of the organophosphorus π-conjugated systems. The specific properties of these complexes make them valuable materials for organic light-emitting diodes and interesting building blocks for the tailoring of novel NLO-phores.  相似文献   

6.
The reactions of carbon centered radical pairs often involve diffusion controlled combination and/or disproportionation reactions which are non-selective. A triplet geminate pair of radicals is produced by the photolysis of suitable ketones. The reactions of such geminate pairs can be controlled though the application of supramolecular concepts which emphasize non-covalent interaction to "steer" the geminate pair toward a selected pathway. In addition, "superdupermolecular" concepts, which emphasize the control of radical pair reactions through the orientation of electron spins, can be employed to further control the course of geminate pair reactions. Examples of control of a range of the selectivity of geminate radical combinations, which form strong covalent bonds, through supramolecular and superdupermolecular effects will be presented for the photolysis of ketones adsorbed in the supercages of zeolites.  相似文献   

7.
Concepts and techniques of supramolecular chemistry are applied to the century-old chemistry between CO2 and amines to design novel sensing systems and nanoscale, self-assembling polymeric materials and networks.  相似文献   

8.
Main group supramolecular chemistry   总被引:1,自引:0,他引:1  
Metal directed self-assembly has yielded a wide array of two- and three-dimensional structures with fascinating new chemical properties. These structures have typically been prepared utilizing transition metals as directing units, owing to the well-defined coordination preferences these metals exhibit. An area of growing research interest involves the preparation of structures containing main group elements as directing units. This tutorial review surveys the wide range of structure types available through this approach, specifically covering unique structure types accessible from the unusual coordination geometries often exhibited by the elements in Groups 12-17 of the periodic table. This review should be of interest to supramolecular and main group chemists, and researchers in the fields of crystal engineering, host-guest chemistry, and molecular recognition.  相似文献   

9.
超分子化学发展简介   总被引:6,自引:0,他引:6  
徐家业 《有机化学》1995,15(2):133-144
本文综述了超分子化学的定义 , 范围及内容. 着重介绍了分子识别, 分子自组装, 超分子催化, 超分子器件及超分子材料等概念. 对由此可能形成的新的前沿科学如分子电子学, 分子离子学, 分子光子学及超分子工艺学等作了扼要介绍 .  相似文献   

10.
An Ag (I) dimer featuring a bridging phosphane ligand acts as an adaptive molecular clip for the coordination-driven synthesis of pi-stacked metallocyclophanes.  相似文献   

11.
Multivalency is a powerful and versatile self-assembly pathway that confers unique thermodynamic and kinetic behavior onto supramolecular complexes. The diversity of the examples of supramolecular multivalent systems discussed in this perspective shows that the concept of multivalency is a general phenomenon, and that any supramolecular interaction can be employed in multivalent displays to attain the attractive aspects characteristic of multivalent interactions. After a general introduction reviewing the general aspects of multivalency, a number of different supramolecular multivalent complexes are discussed that highlight the different features of multivalent interactions. In contrast to the many biochemical multivalent interactions, supramolecular multivalent interactions are ideal to attain a quantitative and fundamental understanding of multivalency. Several examples in which multivalency has been utilized in supramolecular nanofabrication schemes are described in detail.  相似文献   

12.
Emerging supramolecular chemistry of gases   总被引:1,自引:0,他引:1  
Molecular recognition of gases is an emerging area of chemistry. Supramolecular chemistry helps us to understand how gases interact with biological molecules and offers delicate insights into the mechanisms of their physiological activity. Principles of molecular recognition have been used for gas sensing, and have provided fundamental knowledge about the structure and dynamics of receptor-analyte complexes, and novel materials for gas sensing and storage have been developed. Supramolecular chemistry is also enabling us to learn how to transform gases into synthetically useful reagents. The rational design of novel catalysts for gas conversion and, more recently, encapsulation complexes with gases open novel directions in preparative synthetic chemistry.  相似文献   

13.
Halogen bonding is the noncovalent interaction where halogen atoms function as electrophilic species. The energetic and geometrical features of the interaction are described along with the atomic characteristics that confer molecules with the specific ability to interact through this interaction. Halogen bonding has an impact on all research fields where the control of intermolecular recognition and self-assembly processes plays a key role. Some principles are presented for crystal engineering based on halogen-bonding interactions. The potential of the interaction is also shown by applications in liquid crystals, magnetic and conducting materials, and biological systems.  相似文献   

14.
15.
Synthetic and structural studies of Cr horseshoes are reported which show that these compounds demonstrate a rich supramolecular chemistry through H-bonding interactions, and can act as ligands for metal clusters.  相似文献   

16.
We have investigated the exohedral functionalization of [60]fullerene, especially bisaddition; we have revealed the regioselectivity of bisaddition and the properties of obtained bisadducts. The bisaddition without any restriction generally shows low regioselectivity. The electronic and photophysical properties of bisadducts mainly depend on the addition patterns and are almost independent of the nature of addends. We have also attained the regioselective synthesis of bisadducts by controlling the distance and orientation between two reactive species with suitable covalent templates and their application into some functional materials. The synthesis of fullerene‐containing interlocked molecules, such as catenanes and rotaxanes, was accomplished by using a noncovalent interaction, mainly a donor‐acceptor interaction, in addition to the covalent functionalization. The bistable rotaxanes, which can serve as a molecular shuttle or switch, were also successfully prepared. DOI 10.1002/tcr.201000036  相似文献   

17.
Supramolecular polymer networks are three-dimensional structures of crosslinked macromolecules connected by transient, non-covalent bonds; they are a fascinating class of soft materials, exhibiting properties such as stimuli-responsiveness, self-healing, and shape-memory. This critical review summarizes the current state of the art in the physical-chemical characterization of supramolecular networks and relates this knowledge to that about classical, covalently jointed and crosslinked networks. We present a separate focus on the formation, the structure, the dynamics, and the mechanics of both permanent chemical and transient supramolecular networks. Particular emphasis is placed on features such as the formation and the effect of network inhomogeneities, the manifestation of the crosslink relaxation dynamics in the macroscopic sample behavior, and the applicability of concepts developed for classical polymer melts, solutions, and networks such as the reptation model and the principle of time-temperature superposition (263 references).  相似文献   

18.
In this paper we describe the contribution of coordination chemistry to the creation and development of supramolecular chemistry. Both discrete- and infinite buildups are examined. The first group comprises metal-containing host molecules and organic acceptors for metal cations; the second includes coordination polymers, ionic -and liquid crystals. Their potential- and practical applications are briefly explained.  相似文献   

19.
Unlike the case of traditional covalent polymers, the entanglements that determine properties of supramolecular polymers are defined by very specific, intermolecular interactions. Recent work using modular molecular platforms to probe the mechanisms underlying mechanical response of supramolecular polymers is reviewed. The contributions of supramolecular kinetics, thermodynamics, and conformational flexibility to supramolecular polymer properties in solutions of discrete polymers, in networks, and at interfaces, are described. Molecule-to-material relationships are established through methods reminiscent of classic physical organic chemistry.  相似文献   

20.
1,2,5-Chalcogenadiazoles, in particular the tellurium derivatives, are promising building blocks for the assembly supramolecular structures through the formation of the [E-N]2 (E = S, Se, Te) supramolecular synthon. This short account summarizes initial experimental and computational investigations in this area.  相似文献   

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