超分子化学发展简介

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 .     

Fullerodendrimers: a new class of compounds for supramolecular chemistry and materials science applications

Encapsulation of a fullerene sphere in the middle of a dendritic structure prevents unfavorable effects of the C60 unit, such as aggregation or steric hindering. Such fullerodendrimers appear to be promising compounds for materials science applications. On the other hand, fullerodendrons with peripheral C60 subunits or containing a C60 sphere at each branching unit appear to be versatile building blocks for the preparation of fullerene-rich macromolecules with intriguing properties.     

CO2 in supramolecular chemistry: preparation of switchable supramolecular polymers

CO2 gas was used to construct novel types of supramolecular polymers. Self-assembling nanostructures 11 and 13 were prepared, which employ both hydrogen bonding and dynamic, thermally reversible carbamate bonds. As precursors, calixarene ureas 1 and 2 were synthesized, which strongly aggregate/dimerize (K(D)>/=10(6) M(-1) per capsule) in apolar solution with the formation of self-assembling capsules 7 and linear polymeric chains 8, respectively, and also possess "CO2-philic" primary amino groups on the periphery. CO2 effectively reacts with molecules 7 and 8 in apolar solvents and cross-links them with the formation of multiple carbamate salt bridges. Oligomeric aggregate 11 and three-dimensional polymeric network 13 were prepared and characterized by 1H and 13C NMR spectroscopy. The morphology of supramolecular gel 13 was studied by scanning electron microscopy. Addition of a competitive solvent destroyed the hydrogen bonding in assembling structures 11 and 13, but did not influence the carbamate linkers; carbamate salts 12 and 14, respectively, were obtained. On the other hand, thermal release of CO2 from 11 and 13 was easily accomplished (1 h, 100 degrees C) while retaining the hydrogen-bonding capsules. Thus, three-dimensional polymeric network 13 was transformed back to linear polymeric chain 8 without breaking up. Encapsulation and storage of solvent molecules by 11 and 13 was demonstrated. This opens the way for switchable materials, which reversibly trap, store, and then release guest molecules. A two-parameter switch and control over hydrogen bonding and CO2-amine adducts was established.     

Conjugated-carbon nanostructures: Emergences

General emergent features of conjugated-carbon nanostructures are sought. Here, “general” indicates applicability over a broad class of such structures, including graphene and buckytubes, possibly with boundaries or other sorts of defects or decorations, or rather general substructures of graphene or of buckytubes. In addition, “emergent” means that different characteristics and properties are novel and are evidenced from different models, for example, from resonance theory and Hückel theory, preferably with evidence that the features persist upon elaboration. One robust emergent feature is “Dirac cones” in the band structure of graphene and some related materials. Another interesting feature is novel “blended” boundary orbitals that are delocalized longitudinally along the boundary direction while being variably localized in the transverse direction. Furthermore, defects at the ends of polymer chains may be localized or delocalized depending on local features—although the ideas apply more widely to different conjugated-carbon structures including molecules. Explicit formulas are derived to elucidate the asymptotic behavior of unpaired electron density at the ends of selected benzenoid polymers and its relation to the associated HOMO-LUMO gap. Our approach offers a general framework to understand ab initio results, which may, at first sight, appear to be unconventional or counterintuitive to some common ideas of bonding patterns in conjugated carbon nanostructures.     

G-quartets 40 years later: from 5'-GMP to molecular biology and supramolecular chemistry

Molecular self-assembly is central to many processes in both biology and supramolecular chemistry. The G-quartet, a hydrogen-bonded macrocycle formed by cation-templated assembly of guanosine, was first identified in 1962 as the basis for the aggregation of 5'-guanosine monophosphate. We now know that many nucleosides, oligonucleotides, and synthetic derivatives form a rich array of functional G-quartets. The G-quartet surfaces in areas ranging from structural biology and medicinal chemistry to supramolecular chemistry and nanotechnology. This Review integrates and summarizes knowledge gained from these different areas, with emphasis on G-quartet structure, function, and molecular recognition.     

Preface to the special issue: Macrocyclic and supramolecular chemistry

The 14th Conference of Macrocyclic Chemistry and the 6th Conference of Supramolecular Chemistry was held in Northwest Normal University in Lanzhou, Gansu     

Main group supramolecular chemistry

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.     

Coordination chemistry of phosphole ligands: From supramolecular assemblies to OLEDs

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.     

Emerging supramolecular chemistry of gases

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.     

Determining association constants from titration experiments in supramolecular chemistry

The most common approach for quantifying interactions in supramolecular chemistry is a titration of the guest to solution of the host, noting the changes in some physical property through NMR, UV-Vis, fluorescence or other techniques. Despite the apparent simplicity of this approach, there are several issues that need to be carefully addressed to ensure that the final results are reliable. This includes the use of non-linear rather than linear regression methods, careful choice of stoichiometric binding model, the choice of method (e.g., NMR vs. UV-Vis) and concentration of host, the application of advanced data analysis methods such as global analysis and finally the estimation of uncertainties and confidence intervals for the results obtained. This tutorial review will give a systematic overview of all these issues-highlighting some of the key messages herein with simulated data analysis examples.     

Applying reversible chemistry of CO2 to supramolecular polymers

Novel supramolecular, reversibly formed polymers featuring self-assembling capsules have been constructed through chemical fixation of CO2 and hydrogen bonding.     

From supramolecular chemistry towards constitutional dynamic chemistry and adaptive chemistry

Supramolecular chemistry has developed over the last forty years as chemistry beyond the molecule. Starting with the investigation of the basis of molecular recognition, it has explored the implementation of molecular information in the programming of chemical systems towards self-organisation processes, that may occur either on the basis of design or with selection of their components. Supramolecular entities are by nature constitutionally dynamic by virtue of the lability of non-covalent interactions. Importing such features into molecular chemistry, through the introduction of reversible bonds into molecules, leads to the emergence of a constitutional dynamic chemistry, covering both the molecular and supramolecular levels. It considers chemical objects and systems capable of responding to external solicitations by modification of their constitution through component exchange or reorganisation. It thus opens the way towards an adaptive and evolutive chemistry, a further step towards the chemistry of complex matter.     

Halogen bonding in supramolecular chemistry

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.     

Carbon dioxide and supramolecular chemistry

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.     

Halogen bonding: a paradigm in supramolecular chemistry

The term halogen bonding describes the tendency of halogen atoms to interact with lone pair possessing atoms. The binding features and structural properties of halogen bonding are discussed and applied to drive the intermolecular self-assembly of hydrocarbons and perfluorocarbons in chemo-, site-, and enantioselective supramolecular synthesis. The halogen bonding is thus an effective and reliable tool in crystal engineering at the disposal of the supramolecular chemist.     

Analytical supramolecular chemistry: Colorimetric and fluorimetric chemosensors

Chemical sensing using indicators, or chemosensor, has rapidly developed over the past decades. Its chemistry covers a wide range of scientific fields, in which analytical and supramolecular chemistry are key ideas to create functional and smart chemosensors. The principle of such a chemosensor design consists of three major processes: (1) to separate analytes, (2) to capture a specific analyte from a complex mixture, and (3) to output a signal from a [chemosensor•analyte] complex. In this review, “Analytical Supramolecular Chemistry” as a new scientific area was proposed, enabling us to promote deep insights into the mechanistic understanding of chemosensors. This review describes the interesting and representative chemosensors involving significant photochemical and photophysical processes and recent our advances in analytical supramolecular chemistry.     

Physical chemistry of supramolecular polymer networks

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).     

Physical organic chemistry of supramolecular polymers

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.     

The supramolecular chemistry of 1,2,5-chalcogenadiazoles

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.