硝基芳环和硝基杂芳环中氢的替代亲核取代

氢的替代亲核取代反应(VNS)是与硝基芳环的亲电反应、亲核反应不同的一种新反应. 将VNS与硝基芳环的亲电反应、亲核反应做比较, 阐述了VNS的定义; 通过对竞比实验、速控步骤和动力学同位素效应的分析, 解释了VNS的反应机理; 分别从硝基芳环的结构、亲核试剂的类型和反应条件三方面讨论了影响VNS定位效应的因素; 介绍了VNS反应的应用, 尤其是VNS胺化反应在军事化学中的实际应用.     

三氯化铁催化Biginelli型反应合成芳亚甲基稠环嘧啶酮

嘧啶酮及其官能化衍生物常具有重要生理活性,因此该类化合物的合成受到了众多化学家的关注.本工作以三氯化铁催化芳醛、脲(硫脲)和环戊酮的"一锅化"Biginelli-type缩合反应,在无溶剂、无保护的条件下合成了一系列芳亚甲基稠环嘧啶酮化合物.该方法所用催化剂经济易得,且催化剂用量较少,反应条件温和,产率较高.     

KF-Al2O3催化下3-芳基-3-(5，5-二甲基-3-羟基-2-环己烯-1-酮-2-基)丙酰胺衍生物的合成

芳醛、5，5—二甲基—1，3—环己二酮、丙二酸亚异丙酯、芳胺在KF-Al2O3催 化下，在DMF中反应生成3—芳基—3—(5，5—二甲基—3—羟基—2—环己烯—1— 酮—2—基)丙酰胺衍生物，产率良好。     

O2促进下五元环烯胺的C—H亚胺化(英文)

报道了一个O₂促进下五元环烯胺的C—H亚胺化反应.在微波辐射下,季酮酸或1,3-环戊二酮衍生的烯胺酮、芳酮醛水合物和芳胺三组分参与的无金属催化反应进展顺利,以良好的产率和完全的立体选择性得到了一系列α-烯胺基-α-芳酰基亚胺衍生物.在该反应过程中,空气充当绿色氧化剂,水是唯一的副产物.     

4-甲基-3-硝基苯甲腈和2-甲基-5-硝基苯甲腈的合成与表征

4-甲基-3-硝基苯甲腈和2-甲基-5-硝基苯甲腈是重要的有机合成中间体[1,2],因其芳环上具有硝基和氰基两个第二类取代基,同时又有一个可参与反应的甲基而使得这两个化合物在有机合成领域有着广泛的应用前景.芳环上的甲基可以氧化为酸,也可进一步反应形成酰氯、酯等功能基;芳环上的氰基可水解成羧基,也可以与叠氮钠在Lewis酸催化下形成具有生物活性的四唑衍生物;芳环上的硝基经还原可形成氨基,如4-甲基-3-硝基苯甲腈通过化学反应可环合形成药物中间体6-氰基吲哚[2～4].     

固载化聚乙二醇的催化作用

本文报道了聚苯乙烯固载聚乙二醇三相催化剂在卡宾的生成、酯化、假性紫罗兰酮、二茂铁、芳氧乙酸、对硝基茴香醇的合成和C、N-烃基化等反应中的应用，并对其催化机理进行了探讨．     

芳香胺参加的Mannich反应(Ⅱ)——用芳胺盐酸盐合成β-芳胺基酮

室温时芳香胺盐酸盐与甲醛、烷基芳基酮在HCl(气)-C₂H₅OH溶液中可以直接发生Mannich反应,生成β-芳胺基芳酮。这是继文献[1]之后,通过Mannich反应直接合成β-芳胺基芳酮的一个新方法。产率与文献[1]相近或略高。脂肪酮如丙酮、丁酮、甲基异丙基甲酮、甲基异丁基甲酮;环酮如环己酮、环庚酮,同样能发生上述反应。用HNMR谱测定了不对称酮与芳胺及甲醛进行Mannich反应所得到的β-芳胺基脂酮的结构。这一事实说明在室温及酸性条件下,可以用芳胺一步直接合成β-芳胺基酮,其反应机理仍符合一般公认的Mannich反应机理。     

酰氨基硫脲及其相关杂环衍生物的研究(Ⅹ)——1-(4′-吡啶甲酰基)-4-芳酰胺基硫脲类化合物环化反应的研究

本文研究1-(4′-吡啶甲酰基)-4-芳酰胺基硫脲(Ⅰ)在碱催化条件下的环化反应。结果表明,当(Ⅰ)芳环连接吸电子基如硝基、卤素或推电子取代基如甲基和甲氧基等时,均环化为3-(4′-吡啶基)-4-芳酰基-1,2,4-三唑啉-5-硫酮(Ⅱ),通过质谱裂解碎片分析确定其结构,并初步评价部分化合物对结核菌的抑制作用。     

Pd/C催化氢化芳香族硝基化合物合成芳胺

以5%Pd/C为催化剂,芳香族硝基化合物在温和条件(30℃,H2/0.1 MPa)下还原成芳胺。研究了芳环上的取代基对催化加氢反应的影响。结果表明:对位取代的芳硝基化合物的加氢反应速率为:HCH3CO2CH3CF3FOCH3;间位取代芳硝基化合物加氢反应速率为:HCH3CF3FCO2CH3OCH3CN;邻位取代芳硝基化合物加氢反应速率为:HCF3CH3OCH3FCO2CH3CN。     

一叶秋碱A环的引入

本文报导了在一叶 碱全合成的最后阶段中进一步引入A环的方法, 用LDA和其它试剂处理共轭环酮形成Michael加成产物, 同样共轭环酮与醋酐作用, 在170℃经5小时反应, 发生高温裂介, 并形成一芳环, 共轭环酮与乙氧基乙炔锂盐反应, 可得到与天然一叶 碱等同的化合物.     

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.     

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。     

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.

     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

解决能源问题的新途径--光解水制氢的研究

面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。