Tetrathiafulvalene Belts with Large Cavities

The latest member of the cyclophane family, the macrotricyclic tetrathiafulvalene (TTF) “belt”, is now available. A general synthetic strategy for the construction of tetraconnected belt-type TTFs (shown schematically) has been developed, made possible by the use of a TTF with two different protecting groups. In the solid-state structure of one of the three TTF-belts prepared two chloroform molecules reside inside the spacious cavity.     

Supramolecular Inorganic Chemistry: Small Guests in Small and Large Hosts

A key reaction in the biological and material world is the controlled linking of simple (molecular) building blocks, a reaction with which one can create mesoscopic structures, which, for example, contain cavities and display specifically desired properties, but also compounds that exhibit typical solid-state structures. The best example in this context is the chemistry of host–guest interactions, which spans the entire range from three- and two-dimensional to one- and “zero-dimensional”, discrete host structures. Members of the class of multidimensional compounds have been classified as such for a long time, for example, clathrates and intercalation compounds. Thus far, however, there are no classifications for discrete inorganic host–guest compounds. The first systematic approach can be applied to novel polyoxometalates, a class of compounds which has only recently become known. Molecular recognition; tailor-made, molecular engineering; control of fragment linkage of spin organization and crystallization; cryptands and coronands as “cages” for cations, anions or anion–cation aggregates as sections of ionic lattices; anions within anions, receptors; host–guest interactions; complementarity, as well as the dialectic terms reduction and emergence are important terms and concepts of supramolecular inorganic chemistry. Of particular importance for future research is the comprehension of the mesoscopic area (molècular assemblies)—that between individual molecules and solids (“substances”)—which acts in the biological world as carrier of function and information and for which interesting material properties are expected. This area is accessible through certain variations of “controlled” self-organization processes, which can be demonstrated by using examples from the chemistry of polyoxometalates. The comprehension of the laws that rule the linking of simple polyhedra to give complex systems enables one to deal with numerous interdisciplinary areas of research: crystal physics and chemistry, heterogeneous catalysis, bioinorganic chemistry (biomineralization), and materials science. In addition, conservative self-organization processes, for example template-directed syntheses, are of importance for natural philosophy in the context of the question about the inherent properties of material systems.     

Supramolecular Aggregates of Dendritic Cyclophanes (Dendrophanes) Threaded on Molecular Rods with Steroid Termini

Multinanometer-sized assemblies with molecular weights exceeding 14 000 are obtained by the threading of two dendritic cyclophanes (dendrophanes) onto molecular rods in which two testosterone termini are attached by rigid spacers to a central phenyl ring bearing two quaternary ammonium side chains. The formation of these structurally defined aggregates, in which the dendrophanes preferentially encapsulate the steroid termini (see picture), is driven by a combination of apolar interactions, hydrophobic desolvation, and ion pairing, and depends strongly on the length of the spacer.     

卤键在超分子化学中的应用进展

卤键是指作用在卤原子(路易斯酸)和具有孤对电子的原子或π电子体系(路易斯碱)之间的新型弱相互作用,其在超分子多维自组装和分子识别(如超分子催化、超分子选择拆分、超分子传感)等领域有着广泛的应用。本文介绍了卤键的类别、特性、功能及在超分子化学结构与功能领域中的应用。     

Supramolecular Chemistry In Silico

Computational protocols capable of modelling supramolecular complexes have been evaluated. The complexation of cations by crown ethers and quaternary ammonium ions by an oxacalix[3]arene are presented as examples. In the latter case reliable qualitative results were obtained using the semi-empirical PM3 method where guest LUMO and electrostatic potential energies have been shown to correlate with experimental binding data. The optimal method for more accurate results combines semi-empirical equilibrium geometry and property calculations with single point energy calculations at the HF/6–31G* or BP/6–31G* quantum mechanical level.     

Helical Coordination Polymers with Large Chiral Cavities

A quarter of the unit cell volume of [{Ni(4,4′‐dipy)(3‐nitrobenzoate)₂(MeOH)₂}_n], which crystallizes in the form of helices, is occupied by large chiral cavities (400–500 ų). The cavities are capable of encapsulating not only single molecules, but also face‐to‐face dimers of nitrobenzene (see stick model). 4,4′‐dipy=4,4′‐bipyridine.     

超分子化学在药物共晶中的应用

药物共晶是一种新兴的药物晶型, 一个给定的活性药物分子通过形成共晶, 一方面可以大大丰富其结晶形式, 另一方面可以改善其物化性质及临床疗效. 本文从超分子化学的角度对药物共晶进行了综述, 列举了一系列通过氢键超分子合成子进行药物共晶设计和制备的研究实例, 旨在促进超分子化学和药学的交叉融合.     

超分子高分子化学进展

综述了超分子高分子化学近年来的进展,着重介绍固相聚合和毛杆高分子等方面的最新研究成果及应用展望,对超分子高分子化学的主要研究方法也作了扼要的介绍。     

杯芳烃对铁的配位及其超分子化学研究进展

介绍了近年来杯芳烃对铁的配位及其超分子化学的研究进展,讨论了杯芳烃对铁的配位结构及其超分子作用机理.并对"杯芳烃-铁"配位及其超分子化学的研究动向作了展望.     

Self-Assembly of a Three-Dimensional [Ga6(L2)6] Metal–Ligand “Cylinder”

A near trigonal antiprism with metal–metal distances in the nanometer regime is formed by the six metal ions in the crystalline, homochiral [Ga₆(L²)₆] (see structure). This metal–ligand “cylinder” is based on a threefold symmetric, β-diketone ligand, and represents a new geometry for metal–ligand clusters.     

主族金属有机超分子化学进展

以有机主族金属化合物为基本单元进行的超分子自组装是近年来超分子化学的研究方向之一。本文主要对6种主族p区重金属(铟、铊、锡、铅、锑及铋)的典型有机金属超分子的自组装进行探讨和总结。     

Organizational Forms of Matter: An Inorganic Super Fullerene and Keplerate Based on Molybdenum Oxide

Plato and Kepler would have been pleased . Despite the large number of atoms present the cluster anion 1 resembles an icosahedral-type structure. This represents definitively an unprecedented event in chemistry! The structure is made up of 12 {Mo₁₁} fragments such that the fivefold symmetry axes are retained in the resulting spherical object. As an inscribed icosahedron can be recognized in the spherical shell of 1 (see picture), similarities with Kepler's famous shell model of the cosmos can be seen.     

Anion Control in the Self-Assembly of a Cage Coordination Complex

An anion is encapsulated in the center of the new cage compound [Ni₆(atu)₈X]X₃ (X=Cl—for the structure see picture—or Br; Hatu=amidinothiourea). A combination of Lewis acid–base and hydrogen-bonding interactions cause the square-planar [Ni(Hatu)₂]²⁺ units, after deprotonation, to assemble to form this compound. A remarkable feature is the anion dependence of the cage formation; nitrate, acetate, and perchlorate are unsuitable as templates.     

Supramolecular Daisy Chains

Our childhoods may be recalled when a self-complementary cation, endowed with both a dibenzo[24]crown-8 macroring and a secondary dialkylammonium sidearm, self-assembles to form a two-component supramolecular architecture that is reminiscent of a daisy chain (depicted schematically on the right). This daisy-chain-like superarchitecture is stabilized by a combination of [N⁺−H⋅⋅⋅O] hydrogen bonds and aryl–aryl stacking interactions.     

Carbohydrate Recognition through Noncovalent Interactions: A Challenge for Biomimetic and Supramolecular Chemistry

Carbohydrates are not always as “sticky” as one might expect . Even in organic solvents they are difficult targets for the supramolecular chemist, due to their complex, three-dimensional structures. In their natural environment (water) they are especially elusive, presenting challenges which will occupy synthetic and theoretical chemists for some time to come. The complex of an octaamide supramolecular receptor with β-D -glucopyranose, which binds through apolar and polar contacts, is shown.     

A self-assembling metallosupramolecular cage based on cavitand-terpyridine subunits

Metal-directed self-assembly of a terpyridyl-functionalized cavitand yields a large hexameric coordination cage.     

Porous Colloidal Hydrogels Formed by Coordination-Driven Self-Assembly of Charged Metal-Organic Polyhedra

Introduction of porosity into supramolecular gels endows soft materials with functionalities for molecular encapsulation, release, separation and conversion. Metal-organic polyhedra (MOPs), discrete coordination cages containing an internal cavity, have recently been employed as building blocks to construct polymeric gel networks with potential porosity. However, most of the materials can only be synthesized in organic solvents, and the examples of porous, MOP-based hydrogels are scarce. Here, we demonstrate the fabrication of porous hydrogels based on [Rh₂(OH-bdc)₂]₁₂, a rhodium-based MOP containing hydroxyl groups on its periphery (OH-bdc=5-hydroxy-1,3-benzenedicarboxylate). By simply deprotonating [Rh₂(OH-bdc)₂]₁₂ with the base NaOH, the supramolecular polymerization between MOPs and organic linkers can be induced in the aqueous solution, leading to the kinetically controllable formation of hydrogels with hierarchical colloidal networks. When heating the deprotonated MOP, Na_x[Rh₂₄(O-bdc)_x(OH-bdc)_24-x], to induce gelation, the MOP was found to partially decompose, affecting the mechanical property of the resulting gels. By applying a post-synthetic deprotonation strategy, we show that the deprotonation degree of the MOP can be altered after the gel formation without serious decomposition of the MOPs. Gas sorption measurements confirmed the permanent porosity of the corresponding aerogels obtained from these MOP-based hydrogels, showing potentials for applications in gas sorption and catalysis.     

界面超分子聚合

超分子聚合物诞生于高分子化学与超分子化学的交叉融合,一般是指单体间通过非共价键作用连接形成的聚合物,并在溶液或体相中表现出类似聚合物的性质。目前超分子聚合物一般通过均相溶液聚合制备得到,但溶液中的超分子聚合是一个自发的组装过程,具有浓度依赖性,组装过程不易可控。为解决此问题,研究人员可以将超分子聚合从均相溶液转移到界面,在界面上可控地制备超分子聚合物。通过界面聚合制备超分子聚合物具有一些独特的优势,如可以制备得到分子量更高的超分子聚合物,易于制备一些缺陷少、面积大、有序的二维超分子聚合物等。本文基于在液-液、气-液和固-液三种界面上制备超分子聚合物的一些代表性工作,介绍了界面超分子聚合方法和应用,并展望其未来发展。     

Exploiting Cavities in Supramolecular Gels

Endowing supramolecular gelators with cavities opens up a number of opportunities not possible with other gel systems. The well‐established host–guest chemistry of cavitands can be utilized to build up and break down gel structures, introduce responsive functionalities, or enhance selectivity in applications such as catalysis and extraction. Cavity‐containing gelators provide an excellent case study for how different aspects of supramolecular chemistry can be used intelligently to create responsive materials.