硫叶立德参与的Domino环化反应

硫叶立德参与的Domino环化反应在有机合成中具有重要的意义,能够方便地从简单的原料出发,高效地构建多个化学键,合成具有结构多样性和复杂性的有机分子,硫叶立德参与的Domino环化反应被化学界广泛地关注.综述了近年来硫叶立德参与的Domino环化反应合成三元环、五元环、六元环和多元并环类化合物的研究进展.     

有机纳米环/格的研究进展

径向共轭的碳纳米环作为碳纳米管的纳米片段,在合成化学、立体化学、超分子化学和材料科学领域引起了极大的关注.从几何结构角度来看,纳米环的结构分为单环纳米环和多环纳米环.其中,单环纳米环的构建模块主要有苯或多环芳烃以及大环,与以苯或多环芳烃为模块构造的单环纳米环相比,以大环为构建模块的单环纳米环和多环纳米环不仅具有特殊的拓扑结构还具有较高的荧光量子产率、较大的空腔等特点.目前这类具有拓扑结构的纳米环分子在主客体掺杂、储能材料、多孔和有机光电材料等领域体现出重要的研究价值.因此本综述将重点对卟啉类单环纳米环、“8”字型纳米环、纳米格以及更复杂的碳纳米笼的合成方法进行全面的综述.     

拓扑结构高分子的高效“点击”合成

树枝状、梳形、超枝化、星形、及H形等支链结构和环形、多环形等结构的拓扑高分子具有不同于直链结构高分子的独特性能,是一类在材料改性、纳米科技和生物医药等领域有着重要应用前景的新型功能性聚合物材料,日益受到人们的重视,但其复杂的结构导致它们的合成非常繁琐并因此束缚其实际应用.具有定量、快速、高效和高选择性、反应条件温和、产物单一、易于分离等特点的点击反应(click reaction)的应用极大地推动了拓扑结构高分子合成方法的发展.本文就炔/叠氮1,3-偶极环加成反应(CuAAC)、硫醇-烯/炔、胺-丙烯酸酯、Diels-Alder环加成等点击反应应用于树枝状、超枝化、环形、星型等拓扑结构高分子的合成做一简要介绍,并提出了进一步的研究方向.     

通过苄醇与炔烃的环化反应快速高效构建茚及螺环茚

作为一类重要的碳环化合物,茚、螺环茚及其衍生物常见于各种天然产物骨架结构中,并作为合成中间体广泛地应用于材料、医药、有机不对称合成等领域.在路易斯酸TiCl_4或AlCl_3作用下,二苯甲醇或芳基取代环醇等苄醇通过生成碳正离子中间体,与炔烃进行环化反应高效合成多种茚及螺环茚.该反应仅需30 min,反应过程中完成了2个新C—C键的构建,对具有各种取代基的炔烃均有较好的适用性.芳基取代的环丁醇、环己醇、环庚醇、环辛醇以及环十二醇都可以适用于该方法,多样性地构建多种有合成价值的螺环骨架.该方法具有操作简便、反应时间短、条件温和等优点.     

单分散共轭齐聚物的合成方法

简要介绍了线性、星形和环状单分散共轭齐聚物的主要合成方法,并对不同方法的优缺点做了简要评述.其中,线性单分散共轭齐聚物的合成方法主要有4种,即控制聚合方法,发散合成方法,发散/收敛合成方法和指数增长合成方法.在星状单分散共轭齐聚物方面,主要介绍了两种苯环成环反应的应用.环状共轭齐聚物的合成主要介绍了聚合过程中的成环反应、线性共轭齐聚物的分子内环化反应和模板导向环化反应.     

取代邻苯二腈的合成

在室温条件下合成了一系列芳氧基邻苯二腈化合物,应用无素分析、1HNMR、IR确定了它们的结构,讨论了不同取代基对反应的影响.结果表明,酚的芳环上有推电子基时反应容易进行;酚的芳环上有拉电子基时反应慢或不反应.     

瑞香烷型二萜天然产物的合成进展

瑞香烷型二萜类天然产物拥有5/7/6三环骨架的复杂分子结构, 含有多个手性中心, 通常在C3、C4、C5、C9、C13、C14、C20等位置含有手性羟基; 其中, 诸多化合物在C9、C13、C14位置的手性羟基之间形成特定的原酸酯结构. 该类天然产物在抗HIV、抗癌、抗白血病、亲神经性、杀虫、细胞毒性等方面显示显著的生物活性. 瑞香烷型的密集的高氧化数的多环骨架和其引人注目的生物活性吸引了众多研究者的合成兴趣, 尽管迄今为止成功的全合成报道依然鲜见, 但合成化学家对其多环骨架的构建已发展了大量有益的策略和方法, 在此对相关合成工作进行归纳综述.     

氮宾/炔烃复分解串联反应研究进展（英文）

在过去的几十年中,氮宾催化转化作为一类直接构建C—N键的高效反应得到了飞速发展,并被广泛应用于含氮杂环化合物的合成.虽然已有多种类型的氮宾前体被报道,并通过各类催化转化反应在构建结构多样性杂环化合物分子中起到了至关重要的作用,然而,氮宾的反应类型还是局限于胺化反应、氮杂环丙烷化反应、磺化反应等有限的几类反应.基于氮宾前体、催化策略(或者催化剂)以及复杂分子合成的相关综述已有很多报道,这篇综述聚焦氮宾与炔烃的加成反应,主要是氮宾/炔烃复分解串联反应.这类反应可以快速合成具有结构多样性的多环、稠环和螺环类含氮杂环类化合物.     

Lucidone和Methyl Lucidone的简洁合成

报道了lucidone和methyl lucidone的简洁合成,其关键步骤为方酸二甲酯的还原/重排"一锅"反应和单甲氧基环丁烯二酮的达森/扩环反应.Lucidone的合成经过两步反应以46%的总收率实现.Methyl lucidone的合成经过三步反应以43%的总收率完成.     

环稠卟啉合成的研究进展

利用卟啉大环的碳架组成及其连带成分进行各种环合反应是构建环稠卟啉分子的有效方法. 基于这一合成策略, 概述了近年来通过卟啉分子的结构修饰完成环稠卟啉合成的最新研究进展.     

利用手持技术改进测定乙醇分子结构实验

利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。     

光谱仪测试范围的扩展

由于石化行业的生产需要，其材质的使用具有多样性和广泛性，经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识，根据光谱仪的测试能力及标样的采集，实现了一个或几个元素测量范围的扩展，并对其测量的影响因素进行了研究。     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin

The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

物质分配系数的测定实验改进

实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。     

Calculation of enthalpies of hydrogenation of hydrocarbons

Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。