2‐(Arylamino)aryliminophosphoranes from 2‐nitrodiarylamines

Deoxygenation of 2‐nitrodiarylamines by triphenylphosphine is presented as an efficient method for synthesis of 2‐(arylamino)aryliminophosphoranes, useful as starting materials in the synthesis of benzannulated nitrogen heterocycles. The reaction is complementary for the known synthesis of aryliminophosphoranes from 2‐nitrosodiarylamines giving rise to obtain the title products in the broader scope. The presented protocol is simple and efficient although limited to secondary 2‐nitrodiarylamines.     

Three-Component Reaction of Triphenylphosphine,Dialkyl Acetylenedicarboxylates,and Heterocyclic Rings and the Related Iminophosphoranes

Crystalline phosphorus ylides are obtained in excellent yields from the 1:1:1 addition reaction of triphenylphosphine, dialkyl acetylenedicarboxylate, and NH acids, such as 2-aminothiazole and 2-aminobenzothiazole. These stabilized phosphoranes undergo a smooth intramolecular reaction in boiling toluene to produce aryliminophosphoranes in excellent yields.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

Simultaneous spectrophotometric determination of molybdenum and selenium,and of molybdenum and tellurium

A method is reported for the extraction of molybdenum-phenylfluorone by chloroform. The extraction is complete whether perchlorate ions are present or not but the extractions in the presence of perchlorate ions gave a somewhat more sensitive procedure for the spectrophotometric determination of molybdenum in the solvent phase as the molybdenum-phenylfluorone complex.A procedure is reported for the simultaneous determination of molybdenum and selenium, and molybdenum and tellurium. The method involves first the formation and solvent extraction of the molybdenum-phenylfluorone complex by chloroform in the presence of perchlorate ions, followed by determination of selenium in the remaining aqueous phase as selenium-diethyldithiocarbamate complex after solvent extraction with 2-ethyl-1-hexanol in the presence of perchlorate ions. A similar procedure is reported for the simultaneous determination of molybdenum and tellurium except that in the determination of molybdenum, the phenylfluorone complex is extracted by chloroform in the absence of perchlorate ions. Tellurium is determined in the remaining aqueous phase as tellurium-diethyldithiocarbamate complex after solvent extraction by 2-ethyl-1-hexanol solvent extraction in the presence of perchlorate ions.     

芴-噁二唑类聚合物的合成及光谱特性

通过缩聚反应,制得了高分子量的线型和超支化的芴-噁二唑类聚合物．它们均可溶于常用的有机溶剂。在固态薄膜时,它们的紫外-可见光吸收光谱在大约398nm和376nm处有两个强的吸收峰。它们的薄膜PL光谱在蓝光波长范围内有强发射峰,薄膜PL效率约为16％。电化学测试显示它们的的LUMO能级比芴的均聚物高,而与钙、镁这样典型的阴极材料的功函数较接近．这表明此类聚合物具有较好的电子注入和传输性能。     

聚苯胺/金属纳米粒子复合物的制备及性能

基于国内外最新研究文献及本课题组研究工作,从发展历史、制备方法、多功能性方面系统综述了近年来发展起来的聚苯胺/金属纳米粒子复合物。在聚苯胺基体中引入金属纳米粒子的方法可归纳为3大类：原位复合法、直接共混法和层层自组装法。所形成的有机聚苯胺和无机金属杂化复合物不仅能保留各自原有的特异性能,而且二组分之间还存在着相互协同作用,能够极大地提升基体聚苯胺材料的性能,电导率最高可提高100倍,电氧化催化电流最高可提高10倍。分散在聚苯胺膜中的极少量铂微粒就能使不锈钢板的腐蚀电位稳定在钝化区域。聚苯胺/金属纳米粒子复合物所表现出的突出的固有电导性、优异的反应催化性和极强的金属防腐性,使其跻身于为数不多的新型高性能复合材料之列,显示出了诱人的应用前景。     

卟啉钴分子筛的制备,表征和催化性能的研究

用液－固相分步合成法将新型四卤四甲基卟啉诱捕在经Ｃｏ＾２＋交换的ＮａＸ分子筛超笼内，利用索式提取器洗净分子筛外表面吸附的卟啉后，采用ＵＶ－Ｖｉｓ、ＩＲ、ＳＥＭ、ＤＴＡ、Ｘ射线衍射分析、吸附等手段对诱捕在超笼内的卟啉予以表征。进一步对比研究了卟啉、分子筛和诱捕卟啉分子筛的催化性能。结果表明，卟啉与分子筛结合后，催化活性大大提高。     

Crystal and molecular structure of aroyl- and acetylhydrazones of acet- and benzaldehydes

Aroyl- and acetylhydrazones of acet- (I) and benzaldehydes (IV) and benzoylhydrazones of acet- (II) and benzaldehydes (III) were studied by x-ray structural and quantum-chemical methods in order to establish their structures. Compund (I) was the EEZ structure in the crystal. Calculations and spectral data showed that the EEE form occurs in nonpolar solvents and in the gas phase. According to crystallographic data molecules (I)–(IV) are the E-isomers (relative to the N-N bond) and the hydrazone fragments are planar. Intermolecular N-H...O H-bonds from in the crystals. The data obtained suggest that the majority of acylhydrazones are conformationally rigid on dissolution although exceptions do occur. Apparently the reasons for the difference of acetyl- and benzoylhydrazones in electrocarboxylation reactions are electronic and not steric factors.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 75–81, January, 1991.     

Synthesis and Photochemistry of Diphenylchlorin and Diphenylbacteriochlorin

5, 15-Diphenylporphyrin (DPP), a novel porphyrin model compound, was always inaccessible in quantities suitable for study1 because the difficulty of synthesis. So that the characteristic of this molecule had not been explored until a novel method developed for the preparation of DPP recently2. Therefore it will be possible for the synthesis of DPP-based photosensitizers, and investigation of their photodynamic properties. Here we reported the synthesis of novel photosensitizers 5, 15-diphe…     

聚乳酸及其共聚物的合成和在生物医学上的应用

对近２０年来聚乳酸及其共聚物的合成,聚合机理以及在药物控制释放,骨科固定及组织修复,手术缝合线等领域中的应用作了广泛而深入的总结和评述,预示了聚合物材料的制备及在生物医学领域中的研究开发前景。     

离子的极化和形变

离子的极化和形变是无机化学教学中的一对重要概念,这对概念可以用于解释化合物的结构及许多物理和化学性质。然而一些教科书在介绍这对概念时,大都把极化作用限于阳离子,把形变作用限于阴离子,而忽略了阴离子的极化作用和阳离子的形变作用。同时,在应用这对概念解释化合物结构和性质时,条理上也不十分清晰,甚至还出现自相矛盾的情况,使得学生在学习这对概念时感到困惑。本文介绍了离子的极化和形变这对概念的基本含义,讨论了影响极化能力和形变程度的因素,分析了一些化合物的结构以及溶解度、颜色和热稳定性等物理和化学性质。特别是对一些教学中有争议的问题给出了合理解释。在分析小分子结构时,极化和形变概念的运用可以弥补杂化轨道理论和价层电子对互斥理论的不足。     

Synthesis and characterization of mercuriated copolymers of N-vinylcarbazole and acrylic acid

Both linear and crosslinked copolymers of N-vinylcarbazole and methylacrylate were prepared and mercuriated using mercury trifluoroacetate in tetrahydrofuran (THF) and dichloromethane. The mercuriated copolymers, both linear and crosslinked, were hydrolyzed with sodium hydroxide in a mixture of water and THF. The hydrolyzed mercury loading linear copolymer was soluble in water, and the hydrolyzed mercury loading crosslinked copolymer was a waterabsorbing polymer. The iodization of the hydrolyzed mercuriated copolymers was carried out in water with Kl₃, and the iodization of unhydrolyzed mercuriated copolymers was done in THF with I₂. The conformation of the hydrolyzed mercuriated polymer chains could be changed by changing the pH of the aqueous solution. Both the change of conformations and amounts (%) of mercury loading to the carbazoles affected the fluorescence of the carbazole copolymers. The forms of crosslinked mercuriated copolymers could be changed in different solvents and a change of form could affect the chemical modification of metallated aromatic polymers.     

Sizes of atoms and ions and covalency of bonding in molecules and crystals

A new system of atomic radii for the elements up to barium inclusive is constructed. Values of the radii are chosen so as the dependence between the dissociation energy of diatomic homonuclear molecules and a depth of atom overlapping is monotonous, and the scatter of data is minimal. The depth of overlapping is calculated as a difference between the sum of atomic radii and an experimental interatomic distance. Conclusions are made that: the radii of free atoms and ions are determined by the value of the electron density equal to 0.01 au; they considerably change in molecules and crystals only as a result of the charge transfer from cation to anion; covalent bonding is well described by the overlapping of free atoms (ions), confined by the surface of the given radius, and its energy depends upon the depth of overlapping of valence electron densities of atoms. A method of overlapping atoms is proposed for the approximate estimation of ionic sizes and charges in bound systems.     

汞代N-乙烯基咔唑-丙烯酸共聚物的合成与研究

制备线型和网状N-乙烯基咔唑-丙烯酸甲酯共聚物后,用三氟乙酸汞分别在四氢呋喃(THF)和二氯甲烷中进行汞化反应,得到相应的线型和网状汞代咔唑共聚物。这些共聚物经THF溶解或溶胀后,用氢氧化钠水溶液水解,得到相应的水溶性线型高分子和吸水性网状高分子,憎水性汞代咔唑共聚物在THF中由I₂取代汞;亲水性汞代咔唑共聚物在水溶液中由KI₃取代汞。汞代咔唑高分子链在不同溶剂中可以产生不同的形态变化。     

印楝素的合成、结构修饰及生物活性研究进展

自印楝素被分离鉴定以来, 其广谱而独特的生物活性受到人们的广泛关注, 已成为一种近乎完美的植物源杀虫剂; 且在医药、保健、日化等领域都有广泛的应用．其复杂而独特的分子结构使得科研工作者进行了大量的全合成尝试、结构修饰及构效关系等研究. 综述了印楝素A的片段合成、全合成和印楝素有关的结构修饰以及生物活性等方面的研究进展.     

Synthesis and structure of hydroxyisoxazolidines and derivatives of hydroxylamine and alkenals

The reactions of N-substituted hydroxylamines with alkenals serve as a method for the synthesis of the corresponding 2-substituted 3(5)-hydroxyisoxazolidines. The reaction pathway is determined by the nature of the substituent attached to the nitrogen atom. Ring-chain isomerism has been detected in these newly obtained compoundsTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1270–1276, September, 1987.     

Synthesis and Optical and Redox Properties of Symmetric and Asymmetric BODIPYs

Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

三氯环硼氮烷和聚硼氮烷的合成与表征

以三氯化硼和氯化铵为原料,甲苯为溶剂,高产率(98%)地合成了具有硼和氮的六元环结构的三氯环硼氮烷(1);1分别与正丙胺(Ⅰ)和异丙胺(Ⅱ)反应制得正丙胺基环硼氮烷(1~Ⅰ)和异丙胺基环硼氮烷(1~Ⅱ);1~Ⅰ和1~Ⅱ经过脱胺和热聚合反应制得聚硼氮烷先驱体(2和3).用IR,NMR和XRD等对2和3的组成与结构进行了分析,探讨了聚硼氮烷的胺基取代基对聚硼氮烷聚合反应性及产物结构的影响.研究结果表明,3具有更强的热聚合特性.     

Resurrection and Reactivation of Acetylcholinesterase and Butyrylcholinesterase

Organophosphorus (OP) nerve agents and pesticides present significant threats to civilian and military populations. OP compounds include the nefarious G and V chemical nerve agents, but more commonly, civilians are exposed to less toxic OP pesticides, resulting in the same negative toxicological effects and thousands of deaths on an annual basis. After decades of research, no new therapeutics have been realized since the mid-1900s. Upon phosphylation of the catalytic serine residue, a process known as inhibition, there is an accumulation of acetylcholine (ACh) in the brain synapses and neuromuscular junctions, leading to a cholinergic crisis and eventually death. Oxime nucleophiles can reactivate select OP-inhibited acetylcholinesterase (AChE). Yet, the fields of reactivation of AChE and butyrylcholinesterase encounter additional challenges as broad-spectrum reactivation of either enzyme is difficult. Additional problems include the ability to cross the blood brain barrier (BBB) and to provide therapy in the central nervous system. Yet another complication arises in a competitive reaction, known as aging, whereby OP-inhibited AChE is converted to an inactive form, which until very recently, had been impossible to reverse to an active, functional form. Evaluations of uncharged oximes and other neutral nucleophiles have been made. Non-oxime reactivators, such as aromatic general bases and Mannich bases, have been developed. The issue of aging, which generates an anionic phosphylated serine residue, has been historically recalcitrant to recovery by any therapeutic approach—that is, until earlier this year. Mannich bases not only serve as reactivators of OP-inhibited AChE, but this class of compounds can also recover activity from the aged form of AChE, a process referred to as resurrection. This review covers the modern efforts to address all of these issues and notes the complexities of therapeutic development along these different lines of research.