Arene Phosphorus-Containing Macrocyclic Crown Ethers: Last Studies

Abstract

The data on the synthesis, structures, and chemical properties of macrocyclic compounds containing endo-cyclic atoms of tri- and pentavalent phosphorus are summarized. Methods for the synthesis of the described macrocycles are reported. Peculiarities of structure, chemical properties, particularly formation of complexes, catalytic activity, and practical applications are analyzed. The bibliography includes 155 references.     

Understanding and Manipulating Inorganic Materials with Scanning Probe Microscopes

Scanning probe microscopies, such as scanning tunneling microscopy and atomic force microscopy, are uniquely powerful tools for probing the microscopic properties of surfaces. If these microscopies are used to study low-dimensional materials, from two-dimensional solids such as graphite to zero-dimensional nanostructures, it is possible to elucidate atomic-scale structural and electronic properties characteristic of the bulk of a material and not simply the surface. By combining such measurements with chemical synthesis or direct manipulation it is further possible to elucidate relationships between composition, structure, and physical properties, thus promoting an understanding of the chemical basis of material properties. This article illustrates that the combination of scanning probe microscopies and chemical synthesis has advanced our understanding of charge density waves, high-temperature superconductivity, and nanofabrication in low-dimensional materials. This new approach to studying materials has directly contributed to our knowledge of how metal dopants interact with charge density waves and elucidated the local crystal chemistry of complex copper oxides, microscopic details of the superconducting states in materials with a high superconducting transition I_c, and new approaches to the fabrication of multi-component nanostructures. Coupling scanning probe microscopy measurement and manipulation with chemical synthesis should provide an approach to understanding material properties and creating complex nanostructures in general.     

Nanoscaled Structuring as a Way to Constructing New Solid Substances and Materials

State of the art, prospects of research in the field of the precise solid-phase chemical synthesis of highly organized nanostructured solid substances with various level of structural organization are discussed. The notion of topology is introduced for solid chemical compounds to describe the spatial atomic distribution in a substance synthesized. The processes of superordering of a solid, i.e. the formation (synthesis) of ordered distributions of matter of a certain (nanometric) size, as well as the interrelation between the spatial atomic distribution in a structure synthesized and its properties are studied.     

化学结构正规编码及其信息处理功能

自从计算机在化学领域中应用以来,化学结构的正规编码已广泛用来作为一种化学文献的信息索引,它还在开发化学智能系统中发挥着重要作用。正规编码生成是以化学结构图的拓扑性质为基础的。本文首先概述编码的基本原理及其生成的方法,随后分析这种编码在当今文献数据库、化学反应数据库、分子设计以及合成反应路线规划等化学信息系统中的功能。     

硅氧烷基聚合物电解质*

聚合物锂离子电池的核心技术是研制高离子传导率、适宜机械性能以及化学和电化学性能稳定的聚合物电解质材料。在众多寻求高性能聚合物电解质的研究工作中,由于硅氧烷基聚合物电解质具有灵活多样的分子结构设计、易于合成实施、优异的电化学性能和室温电导率等特点,一直是人们关注的热点领域。本文综述了近年来新型硅氧烷基聚合物电解质的设计与合成的研究工作,重点介绍了采用聚硅氧烷嵌段、接枝聚合物通过共混、互穿网络结构、交联网络结构以及无机-有机复合等方法开展的相关聚合物电解质的研究工作。同时也介绍了聚硅氧烷电解质的研究方法和基于聚硅氧烷电解质的应用研究进展。     

Azo-containing polyurethanes with nonlinear-optical properties

The specific features of nonlinear-optical properties of polymers and the principles of the molecular design of macromolecules containing chromophore groups are considered. Approaches to the design of hydroxyl-containing azo monomers and polyurethanes with nonlinear-optical properties formed on their basis are generalized. The classification of azo-containing polyurethanes in terms of their chemical structure and method of synthesis is suggested, and the structure and nonlinear optical properties of these polymers are discussed.     

苯乙炔基封端聚酰亚胺材料研究进展

在过去二十年中，芳香族聚酰亚胺材料得到越来越广泛的应用，其中苯乙炔基封端的聚酰亚胺材料因其优异的性能成为目前耐高温聚合物材料研究的热点。本文综述了苯乙炔基封端聚酰亚胺材料的研究现状与发展趋势，着重对材料的化学结构设计与制备方法、以及化学结构与性能之间的关系进行介绍。     

Synthesis, Structure, and Chemical Properties of N-Substituted 2(3)-Imino-2,3-dihydrofuran-3(2)-ones. (Review)

Published data on the synthesis, structure, and chemical properties of N-substituted 2(3)-imino-2,3-dihydrofuran-3(2)-ones to 2002 are reviewed     

Synthesis,Structural and Biological Properties of the Ring-A Sulfonamido Substituted Chalcones: A Review

Sulfonamidochalcones continue to assert themselves as versatile synthetic intermedi-ates and several articles continue to appear in literature describing their synthesis, chemical transformation and biological properties. These compounds are not only of interest from the medicinal chemistry context, their conformations and crystalline structures also continue to attract attention to explore non-covalent (intramolecular and intermolecular) interactions, control molecular conformations, and improve their physicochemical and optical properties. Despite an exhaustive list of examples of the ring-A sulfonamide-appended chalcones described in the literature, there is no com-prehensive review dedicated to their synthesis, structural and biological properties. This review focuses attention on the synthesis, structure and biological properties of the ring-A sulfonamide-appended chalcones (o/m/p-sulfonamidochalcones) as well as their potential as non-linear optical materials.     

无机纳米管材料合成进展

无机材料的微观结构决定了材料的许多特性,如传输行为、催化活性、分离效率、粘附、储存和释放动力学。具有管状结构纳米尺度的材料由于其特殊的结构及由此带来的特殊性能正成为一个令人兴奋的化学研究领域。文章综述了近年来无机纳米管材料的合成途径和进展。     

The Construction of New Proteins. Part III. Artificial folding units by assembly of amphiphilic secondary structures on a template

A new general strategy for the construction of artificial proteins with predetermined tertiary structure is presented. Amphiphilic α-helix and β-sheet-forming oligopeptides are assembled on a multifunctional ttemplate molecule which directs the peptide blocks to adopt characteristic folding topologies. The design, synthesis, and conformational properties of these template-assembled synthetic proteins (TASP) are exemplified for βαβ-, α-helix-bundle- and β-barrel-like tertiary structures using specially designed oligopeptides as template molecules. In contrast to linear polypeptide chains of comparable molecular weights, these conceptually novel marcromolecules are readily accessible to chemical synthesis and exhibit excellent solubility in a number of solvents. Experimental evidence is provided for a template-induced intramolecular folding to secondary and tertiary structures in aqueous solutions. This approach opens new prospects for the chemical construction of biomacromolecules with tailormade structural and functional properties.     

Macromolecular systems with the p-type conductivity

General concepts of organic (polymeric) electronics are given, a relationship between chemical structure of semiconducting macromolecular systems and their electronic properties is considered, main approaches to the control of these properties are listed. A relationship between dimensionality of the systems considered (one-, two-, and three-dimensional) and a possibility to control their molecular organization, as well as their practical use are illustrated. Typical representatives of both the linear and branched (two- and three-dimensional) macromolecules, approaches to the synthesis of such macromolecules, their optical and electrical properties, as well as prospective fields of application, are considered.     

Liquid-Phase Synthesis of Iron Oxide Nanostructured Materials and Their Applications

Owing to their high natural abundance, low cost, easy availability, and excellent magnetic properties, considerable interest has been devoted to the synthesis and applications of iron oxide nanostructured materials. Liquid-phase synthesis methods are economical and environmentally friendly with low energy consumption and volatile emissions, and as such have received much attention for the preparation of iron oxide nanostructured materials. Herein, the liquid-phase synthesis methods of iron oxide nanostructured materials including the co-precipitation method, microemulsion method, conventional hydrothermal and solvothermal methods, microwave-assisted heating method, sonolysis method, and other methods are summarized and reviewed. Many iron oxide nanostructured materials, self-assembled nanostructures, and nanocomposites have been successfully prepared, which are of great significance to enhance their structure-dependent properties and applications. The specific roles of liquid-phase chemical reaction parameters in regulating the chemical composition, structure, crystallinity, morphology, particle size, and dispersive behavior of the as-prepared iron oxide nanostructured materials are emphasized. The biomedical, environmental, and electrochemical energy storage applications of iron oxide nanostructured materials are discussed. Finally, challenges and perspectives are proposed for future investigations on the liquid-phase synthesis and applications of iron oxide nanostructured materials.     

Atomic and electronic structure of gold clusters: understanding flakes, cages and superatoms from simple concepts

Atomic structure and electronic structure are intimately interrelated properties of nanoclusters and nanoparticles, defining their stability, electronic, optical and chemical properties, in other words, their usability as potential components for nanoscale devices. This tutorial review attempts to describe the development in understanding the structures of bare and ligand-protected gold clusters over the past decade, based on selected density-functional-theory calculations. This review should be of interest both to newcomers in the field and to an interdisciplinary community of researchers working in synthesis, characterization and utilization of ligand-protected gold clusters.     

Synthesis,properties, and application of polymeric carbon nitrides

The results of theoretical and experimental studies of the structure and properties of poly-meric carbon nitrides are reviewed. Various routes of the synthesis of these compounds using nitrogen-rich precursors, viz., cyanamide, dicyandiamide, carbamide, melamine, etc., are described. Particular attention is paid to the catalytic properties of graphite-like carbon nitrides and methods of their texture and chemical modification. The main trends for the synthesis of meso- and nanostructured materials based on graphite-like carbon nitrides are considered. Prospects of their practical application as efficient photo-, electro-, and heterogeneous metal-free catalysts are discussed.     

Phospholipids as Functional Constituents of Biomembranes

This article describes new methods for the synthesis of biologically active phospholipids. The physical properties of such compounds are directly related to their chemical structure, the position of the substituents esterified with glycerol not only influencing the physical properties but also the biological function of the phospholipids. Phase transitions can be induced by temperature changes and—in biological systems—by changes in the surface charge or the degree of protonation. In model studies, the properties of lipid phases differ sufficiently to influence and control biological membrane processes. Alkyl glycerides can modify the properties of biological membranes quickly and reversibly to increase the permeation of active compounds. An important example is the improved transport of cytostatic drugs across the blood-brain barrier. Knowledge about the substrate specificity of enzymes that metabolize phospholipids allows the synthesis of tailored cytotoxic phospholipids which selectively accumulate in malignant tissues. Thus, the interplay of chemical synthesis and investigations of physical structure lays a foundation for the understanding of simple membrane processes on a molecular level, and the experience gained with such model systems can, in turn, be used to influence natural membranes, such as those of the blood-brain barrier or of tumors, in a directed way.     

以天然矿物为全部硅铝源低成本绿色合成ZSM-5分子筛的研究

ZSM-5分子筛被广泛地应用于催化、吸附分离、离子交换和绿色化工等领域,但目前其合成主要是以无机化学品为硅铝源,从源头来看是非绿色化的过程.我们以热活化的硅藻土和亚熔盐活化的累托土为全部硅铝源,通过调变两种矿物的加入比例调变合成体系的硅铝比,在水热合成体系中制备ZSM-5分子筛.系统地考察模板剂用量、碱度、投料硅铝比、晶化时间等合成条件对产物结构和性质的影响,并对在最优条件下合成的ZSM-5分子筛的物化性质进行了详细地表征,结果表明：以天然矿物为全部硅铝源可以合成出具有较高结晶度、晶粒尺寸约为4 μm的六面体挛晶形貌的ZSM-5分子筛,该分子筛比商业ZSM-5分子筛具有更高的水热稳定性和更优的加氢异构性能.     

仿花瓣表面多功能高分子纳米薄膜的制备

以红玫瑰花瓣为模板, 用纳米压印图案转移法进行仿生合成, 获得具有多功能性的高分子薄膜. 通过将薄膜进行染色, 制得了具有特殊花瓣颜色的人工薄膜, 并探讨了化学色与结构色之间的关系.     

Amorphous copoly(arylene ether ketones): synthesis and properties

The results of research from the scientific school of Academician V. V. Korshak in the field of synthesis and properties of amorphous copolyarylene ether ketones of random and block structure obtained by the reaction of nucleophilic substitution are summarized and analized in the author’s review. The relationship between the properties of copolyarylene ether ketones, their chemical structure, and molecular weight is considered.