4-甲氧基-7H-呋喃[3,2-g][1]苯并吡喃-7-酮制备的新方法

以间苯三酚为起始原料,通过醚化反应、碘化反应、Pechmann反应、偶联反应、水解反应和脱羧反应合成了目标产物4-甲氧基-7H-呋喃[3,2-g][1]苯并吡喃-7-酮。经红外光谱、质谱、核磁共振测试技术对各化合物的结构进行了表征。优化了醚化反应和碘化反应的工艺条件,并探索了通过选择性碘化反应、Pechmann反应和偶联反应来合成目标化合物的可行性。反应均在常压下进行,反应条件温和,后处理相对简单,为呋喃香豆素类化合物的制备提供了新方法。     

1-苯基-3-甲基-4-苯甲酰基吡唑啉酮/PdCl2在温和条件下催化Suzuki偶联反应的研究

考察了商品化的简单非膦配体1-苯基-3-甲基-4-苯甲酰基吡唑啉酮在有氧温和条件下的Suzuki偶联反应活性,探讨了反应温度、反应时间、溶剂以及碱对反应的影响。结果表明,该配体在优化的反应条件下能高效催化不同溴代反应物和氯代反应物与苯硼酸的交叉偶联反应;提高反应温度、延长反应时间和引入质子性极性有机/水混合溶剂有利于偶联反应的进行。     

2-甲基-1,8-萘啶衍生物的甲基溴代反应

报道了2-甲基-1,8-萘啶衍生物的甲基溴化反应,以N-溴代琥珀酰亚胺(NBS)为溴化剂、红外光为引发剂,得到单溴代产物2-溴甲基-1,8-萘啶衍生物及其二溴代副产物2-二溴甲基-1,8-萘啶衍生物,对比了两种不同的反应条件,通过对影响甲基溴化产物产率的反应条件进行优化改进,得到单溴代产物的较优合成条件为:NBS的用量为原料的1.2倍,500 W红外灯为光源,反应时间为2 h。该反应条件下,单溴代产物的产率可达到54.6%。     

相转移条件下Cu(Ⅰ)催化的末端炔的偶联反应研究

本文报道端炔与烯(炔)丙基衍生物在Cu(Ⅰ)催化和相转移条件下发生偶联反应合成1,4-烯炔、二炔化合物的方法。考察了溶剂、催化剂、反应底物、反应时间和温度等多种因素对偶联反应的影响, 用正交试验法优选出最佳反应条件,此反应条件具有条件温和、催化剂用量少、收率高、无烯(炔)丙基重排副产物生成等特点。用此方法合成了十一种1,4-烯炔、二炔化合物。     

间二氟苯溴化反应产物的气相色谱-质谱分析

采用气相色谱-质谱(GC/MS)法对间二氟苯溴化反应产物的组成与结构进行了分析,并对间二氟苯溴化反应的选择性及反应条件进行了初步探讨。结果表明:间二氟苯的溴化反应具有较强的选择性,其主要反应产物为1-溴-2,4-二氟苯,副产物为1-溴-2,6-二氟苯、1-溴-3,5二氟苯及二溴代间二氟苯等溴化物。该反应的反应条件对产物组成有较大影响。     

相转移条件下Cu(Ⅰ)催化的末端炔的偶联反应研究

本文报道端炔与烯(炔)丙基衍生物在Cu(Ⅰ)催化和相转移条件下发生偶联反应合成1,4-烯炔、二炔化合物的方法。考察了溶剂、催化剂、反应底物、反应时间和温度等多种因素对偶联反应的影响, 用正交试验法优选出最佳反应条件,此反应条件具有条件温和、催化剂用量少、收率高、无烯(炔)丙基重排副产物生成等特点。用此方法合成了十一种1,4-烯炔、二炔化合物。     

荧光增白剂4,4′-二(4-磺酸钠苯乙烯基)二苯甲酮的合成

用Heck反应合成了4,4′-二(4-磺酸钠苯乙烯基)二苯甲酮.对Heck反应条件进行了改进,使用壳聚糖负载钯为催化剂并考察了催化剂的回收再利用情况.通过研究影响该反应的各种因素,如反应时间、反应温度、原料配比等,优化了实验条件,得到了较好的结果.     

无催化剂、无溶剂条件下合成螺氧化吲哚衍生物

报道了在无催化剂、无溶剂条件下,靛红、丙二腈和1,3-二羰基化合物在80℃反应温度下,通过"一锅煮"三组分反应合成了螺氧化吲哚衍生物-该法具有反应条件温和、操作简单、产率较高和对环境友好等优点.     

机械研磨法合成5-(2-硝基烷基)米氏酸衍生物

以5-亚烃基米氏酸衍生物与硝基烷烃类化合物在固相机械研磨条件下,在碱存在下,反应合成5-(2-硝基烷基)米氏酸衍生物,探讨了碱、反应物料比等条件对产物产率的影响,优化反应条件为:等物质的量的甲醇钠,反应温度50℃,反应时间30 min.该方法适用于合成多种5-(2-硝基烷基)米氏酸衍生物,为γ-氨基丁酸衍生物的合成提供...     

双膦配体DPPB的铑配合物催化烯烃氢甲酰化反应研究(2000年版)

研究了由 Rh(acac) (CO) 2 和 1 ,4-双 (二苯膦基 )苯 (简称 DPPB)组成的体系对烯烃氢甲酰化反应的催化作用 .考察了反应温度、压力、P/Rh比、催化剂浓度等对 1 -己烯氢甲酰化反应的影响 ,得到了较适宜的反应条件 .在相同条件下比较了该体系催化 1 -己烯、 1 -辛烯、 1 -十二烯的氢甲酰化反应的性能 .结果表明 ,随着底物碳链的增长 ,反应活性呈提高趋势 .实验证明 ,DPPB-铑配合物对苯乙烯的氢甲酰化反应有较高的催化活性和选择性 .     

LOW DENSITY POLYETHYLENE/CLAY NANOCOMPOSITES MODIFIED BY ETHYLENE COPOLYMERS： EFFECTS OF FUNCTIONALIZED SEGMENTS ON MORPHOLOGY

Melt extrusion was used to prepare binary nanocomposites of ethylene copolymers and organoclay and trinary nanocomposites of low-density polyethylene （LDPE）, ethylene copolymer and organoclay. X-ray diffraction （XRD） and transmission electron microscopy （TEM） were used to analyze the structure of the clay phase and the morphology of the nanocomposites. Influences of the comonomer in the copolymer and the content of the copolymer on the morphology of the resulting nanocomposites were discussed. The binary and the trinary composites may form intercalated or exfoliated structures depending on the interaction between the copolymer and the clay layers and the content of the copolymer.     

Applications of Thermal Analysis and Coupled Techniques in Pharmaceutical Industry

Thermal analysis methods are well-established techniques in research laboratories of pharmaceutical industry. The robustness and sensitivity of instrumentation, the introduction of automation and of reliable software according to the industrial needs widened considerably the areas of applications in the last decade. Calibration of instruments and validation of results follow the state of the art of cGMP as for other analytical techniques. Thermal analysis techniques are especially useful for the study of the behavior of the poly-phasic systems drug substances and excipients and find a unique place for new delivery systems. Since change of temperature and moisture occur by processing and storage, changes of the solid state may have a considerable effect on activity, toxicity and stability of compounds. Current requirements of the International Conference of Harmonisation for the characterization and the quantitation of polymorphism in new entities re-enforce the position of thermal analysis techniques. This challenging task needs the use of complementary methods. Combined techniques and microcalorimetry demonstrate their advantages. This article reviews the current use of thermal analysis and combined techniques in research and development and in production. The advantage of commercially coupled techniques to thermogravimetry is emphasized with some examples. This revised version was published online in August 2006 with corrections to the Cover Date.     

Contributions to the Chemistry of the Binary Compounds of the Transition Elements

Phase and structural relationships of the sulfur, selenium, and tellurium compounds of the 4d and 5d transition elements of groups IV to VII of the periodic system are discussed. Homologous elements behave very similarly with respect to the chalcogens, and this is particularly the case for niobium and tantalum, and for molybdenum and tungsten. However, zirconium, niobium, and molybdenum have a greater tendency towards formation of chalcogen-poor phases than their homologues hafnium, tantalum, and tungsten. Subchalcogenides are known only for zirconium and niobium. The number of phases and the tendency towards formation of solid solutions are considerably smaller among the tellurides than among the sulfides and selenides. The crystal structures of the telluride phases also differ from those of the sulfide and selenide phases of analogous composition. In addition, a review of the phase and structural relationships of the arsenic and antimony compounds of the 4d and 5d transition elements of groups V to VII is given.     

Synthesis,analytical characterization and bioactivity of Ag and Cu nanoparticles embedded in poly-vinyl-methyl-ketone films

The electrosynthesis of copper and silver core-shell nanoparticles (NPs) by the sacrificial anode technique, employing tetraoctylammonium (TOA) salts as base electrolyte for the first time, is described. These surfactants were selected because they combine high NP stabilizing power with useful disinfecting properties. The resulting colloids were mixed with a solution of an inert dispersing polymer and used to prepare nanostructured composite thin films. The morphologies and chemical compositions of the nanomaterials were characterized by Transmission Electron Microscopy (TEM) and X-ray Photoelectron Spectroscopy (XPS). The TEM reveals that the average core diameter of the metal NPs ranges between 1.7 and 6.3 nm, as a function of the nature of the metal and of the electrosynthesis conditions, and does not change significantly upon inclusion in the polymer matrix. An appreciable concentration of the metal is detected on the nanoparticle surface by XPS. High-resolution XP spectra indicate that both copper and silver are present at zero oxidation state in all of the materials (colloids and composite films). This demonstrates the high efficiency of the surfactant at controlling the morphology and the chemical composition of the nanodispersed metal in both the as-synthesized colloid and in the polymeric dispersion. The nanocoatings are shown to exert a marked inhibitory effect on the growth of eukaryote and prokaryote target microrganisms, and experimental evidence of a synergic disinfecting effect due to the surfactant and the nanodispersed metal is provided. On the basis of these stability and bioactivity results, it is clear that Cu-NPs and Ag-NPs are suitable for application in disinfecting or antifouling paint and coating formulations.Electronic Supplementary Material Supplementary material is available for this article at Dedicated to the memory of Wilhelm Fresenius     

生物热化学和热动力学研究进展

生命相关过程伴随着极其复杂的化学和物理过程,包含着物质变化和能量转换,其中部分能量不可避免地会以热的形式表现出来。用微量热技术和热动力学方法,研究复杂生命体系和相关反应的热动力学过程,可宏观地、本质地反映生命相关过程的内在规律。本文综述了生物量热学方法和技术在生命科学中的应用,介绍了生物量热技术在生态系统、生物组织和器官、细胞水平、亚细胞水平和分子层面等不同生物层次和结构水平上的研究现状和进展。     

Thermodynamics of dissolving and solvation processes for benzoic acid and the toluic acids in aqueous solution

Experimental data are presented for the solubility in water of benzoic and toluic acids from 5° to 65°C. From the solubility the molality of the monomeric form of the acid is calculated using literature data for both ionization and dimerization of the acid. These data for the monomer combined with data from the literature for vaporization of the solid and ionization in both the gas phase and the aqueous phase yield entropy and enthalpy changes for the solvation of molecular and anionic forms of the acid. A similar procedure is also applied to literature data for the solubility of benzene in water. It is shown that the hydration entropies of the monomeric forms are a linear function of their partial molar volumes. It is concluded that hydration of the undissociated o-toluic acid may be crucial to the increased acidity of that acid compared to benzoic acid.     

Polymorphism and Conformational Equilibrium of Nitro-Acetophenone in Solid State and under Matrix Conditions

Conformational and polymorphic states in the nitro-derivative of o-hydroxy acetophenone have been studied by experimental and theoretical methods. The potential energy curves for the rotation of the nitro group and isomerization of the hydroxyl group have been calculated by density functional theory (DFT) to estimate the barriers of the conformational changes. Two polymorphic forms of the studied compound were obtained by the slow and fast evaporation of polar and non-polar solutions, respectively. Both of the polymorphs were investigated by Infrared-Red (IR) and Raman spectroscopy, Incoherent Inelastic Neutron Scattering (IINS), X-ray diffraction, nuclear quadrupole resonance spectroscopy (NQR), differential scanning calorimetry (DSC) and density functional theory (DFT) methods. In one of the polymorphs, the existence of a phase transition was shown. The position of the nitro group and its impact on the crystal cell of the studied compound were analyzed. The conformational equilibrium determined by the reorientation of the hydroxyl group was observed under argon matrix isolation. An analysis of vibrational spectra was achieved for the interpretation of conformational equilibrium. The infrared spectra were measured in a wide temperature range to reveal the spectral bands that were the most sensitive to the phase transition and conformational equilibrium. The results showed the interrelations between intramolecular processes and macroscopic phenomena in the studied compound.     

宝日希勒褐煤在合成气与复合溶剂系统下的液化性能研究

在合成气（CO+H₂）与复合溶剂（水+有机溶剂）液化系统下研究了气氛、温度、催化剂类型对宝日希勒褐煤转化率、油气水产率和CO转化率等液化特征的影响，从而探讨其液化性能。结果表明，在高含水复合溶剂系统中，合成气气氛、反应温度430-450℃适宜宝日希勒褐煤液化转化，转化率可达到81.15%，油气水产率达到71.53%。该液化系统下，含铁、碱和硫复合型催化剂能有效地提高液化转化率和油气水产率，在430℃催化液化下褐煤转化率达92.27%，油气水产率达79.39%。该催化剂有效促进了煤中大分子的裂解和系统中水煤气变换反应进程，沥青质减少，油含量增多。液化油中多环芳烃衍生物在催化液化过程中向单环芳烃衍生物和烷烯烃转化，分子量降低，提高了油品质量。     

水稻秸秆与PVC塑料共气化过程中钾、钠、氯的迁移行为

采用固定床反应器,结合X射线衍射(XRD)表征和热力学计算研究了水稻秸秆与PVC塑料共气化过程中钾钠氯的迁移和状态变化。结果表明,混合物中氯的释放率与反应温度和PVC塑料的量(氯含量)有关。当反应温度为800~900℃时,PVC的量对混合物中氯元素释放率的影响最为显著;气化温度达900℃时,含PVC 20%(氯含量为11.5%)的水稻秸秆混合物中,氯元素的释放率较纯水稻上升了16.5%。与此同时,氯含量的增加也促进了钾钠在气相中的释放。气化温度为850℃时,当混合物中PVC比例大于20%(氯含量大于11.5%)时,氯对钾钠的气相析出有一定抑制作用;钾钠以KCl和NaCl的形式滞留在固相中,其含量随着混合物中PVC量的升高而降低。     

Recent advances in the diversification of chromones and flavones by direct C-H bond activation or functionalization

Chromone and flavone are both central backbones of natural products and clinical medicines. Synthesis of diversely functionalized chromones and flavones constitutes significant research contents of the modern synthetic science because abundant molecular libraries of such types are crucial in providing candidate compounds for the discovery of new pharmaceuticals and functional materials. The direct C-H bond activation or functionalization on these heterocyclic backbones provides highly powerful tools for the rapid accesses to densely functionalized chromone and flavone derivatives. Considering the importance of the functionalized chromone and flavone compounds as well as the notable advances in the synthesis of such products by direct C-H activation or functionalization, we review herein the research advances in the C-H bond activation and functionalization reactions of chromone and flavones, in hope of showing the current states and promise of the research domain.