聚(4-乙烯基吡啶)硫酸氢盐: 一个新的高效催化剂用于无溶剂条件下合成13-芳香基-茚并 [1,2-b] 石脑油 [1,2-e] 吡喃-12(13H)-酮（英文）

An facile and efficient protocol for the synthesis of 13‐aryl‐indeno[1,2‐b]naphtha[1,2‐e]pyran‐ 12(13H)‐ ones has been developed that proceeds via the one‐pot three‐component sequential reaction of an aromatic aldehyde with β‐naphthol and 2H‐indene‐1,3‐dione under solvent‐free conditions in the presence of a poly(4‐vinylpyridinium)hydrogen sulfate(P(4‐VPH)HSO4) catalyst. The catalyst can be reused several times, making this procedure facile, practical, and sustainable. The simple experimental procedure, solvent‐free reaction conditions, use of an inexpensive catalyst, short react time, and excellent yields are some of the major advantages of this methodology.     

以对二甲苯氧化为对苯二甲酸为例简要综述一级C–H键活化(英文)

The oxidation of para‐xylene to terephthalic acid has been commercialised as the AMOCO process(Co/Mn/Br) that uses a homogeneous catalyst of cobalt and manganese together with a corrosive bromide compound as a promoter. This process is conducted in acidic medium at a high tempera‐ture(175–225 °C). Concerns over environmental and safety issues have driven studies to find mild‐er oxidation reactions of para‐xylene. This review discussed past and current progress in the oxida‐tion of para‐xylene process. The discussion concentrates on the approach of green chemistry in‐cluding(1) using heterogeneous catalysts with promising high selectivity and mild reaction condi‐tion,(2) application of carbon dioxide as a co‐oxidant, and(3) application of alternative promoters. The optimisation of para‐xylene oxidation was also outlined.     

Fe3O4@MCM-48–SO3H:合成苯并[f]色烯并[2,3-d]嘧啶酮的高效、可磁性分离纳米催化剂（英文）

Sulfonic acid groups were grafted onto three different types of synthesized magnetic nanoparticles, namely Fe3O4, Fe3O4@SiO2, and Fe3O4@MCM‐48. The sulfonic acid‐functionalized nanoparticles were evaluated as catalysts for the synthesis of 5‐aryl‐1H‐benzo[f]chromeno[2,3‐d]pyrimidine‐2,4(3H,5H)‐dione derivatives in terms of activity and recyclability. Their catalytic activities were compared with that of the homogeneous acid catalyst 1‐methylimidazolium hydrogen sulfate ([HMIm][HSO4]). The activity of Fe3O4@MCM‐48–SO3H was comparable to those of the other heter‐ogeneous and homogeneous catalysts.     

以对二甲苯氧化为对苯二甲酸为例简要综述一级C–H键活化(英文)

The oxidation of para‐xylene to terephthalic acid has been commercialised as the AMOCO process(Co/Mn/Br) that uses a homogeneous catalyst of cobalt and manganese together with a corrosive bromide compound as a promoter. This process is conducted in acidic medium at a high tempera‐ture(175–225 °C). Concerns over environmental and safety issues have driven studies to find mild‐er oxidation reactions of para‐xylene. This review discussed past and current progress in the oxida‐tion of para‐xylene process. The discussion concentrates on the approach of green chemistry in‐cluding(1) using heterogeneous catalysts with promising high selectivity and mild reaction condi‐tion,(2) application of carbon dioxide as a co‐oxidant, and(3) application of alternative promoters. The optimisation of para‐xylene oxidation was also outlined.     

原位生成的Ph_3C~+均相有机催化剂催化4,4'-芳亚甲基-二(3-甲基-1-苯基-1H-吡唑-5-醇)高效合成（英文）

Trityl chloride(Ph3CCl) efficiently catalyzes the condensation of 3‐methyl‐1‐phenyl‐1H‐pyrazol‐ 5(4H)‐one and aromatic aldehydes under mild and solvent‐free conditions, affording 4,4'‐(arylmethylene)‐ bis(3‐methyl‐1‐phenyl‐1H‐ pyrazol‐5‐ol)s in high to excellent yields and in short reaction time. The presence of the requisite organocatalytic trityl carbocation(Ph3C+) species was confirmed by analysis of infrared, 1H NMR, and ultra violet spectral data. A plausible mechanism was proposed for the reaction based on the observations and literature precedent.     

以聚(4-乙烯基吡啶)硫酸氢盐为催化剂三组分一锅法合成苯并[f]茚并喹啉(英文)

7‐Aryl‐8H‐benzo[f]indeno[2,1‐b]quinoline‐8‐one derivatives were synthesized by means of a one‐pot condensation of 2‐naphthylamine, aromatic aldehydes, and indane‐1,3‐dione in ethanol under refluxing conditions in the presence of poly(4‐vinylpyridinium) hydrogen sulfate, a solid acid catalyst. This method has the advantages of high yield, clean reaction, simple methodology, and short reaction time. The catalyst could be recycled and reused four times without significant loss of activity. The structure of the novel compounds was confirmed by IR, 1H NMR, and 13C NMR spec-troscopy and elemental analysis.     

硅胶键合N-丙基哌嗪n-丙酸钠作为可循环使用催化剂催化4H-吡喃衍生物合成(英文)

Silica‐bonded N‐propylpiperazine sodium n‐propionate(SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H‐benzo[b]pyran derivatives. SBPPSP was used as a recyclable heterogeneous solid base catalyst for the synthesis of 3,4‐dihydropyrano[c]chromenes, 2‐amino‐4H‐pyrans, 1,4‐dihydropyrano[2,3‐c]pyrazoles, and 2‐amino‐4H‐benzo[e]‐chromenes via the condensation reaction of dimedone, ethyl acetoacetate, 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐ one, and α‐naphthol, respectively, with aromatic aldehydes and malononitrile in refluxing aqueous ethanol. The heterogeneous solid base showed similar efficiency when reused in consecutive reactions.     

MgO纳米晶负载镍催化剂用于甲烷蒸汽重整反应(英文)

Nanocrystalline MgO with a relatively high surface area and mesoporous structure was synthesized by a surfactant assisted precipitation method for use as the support of nickel catalysts for steam reforming of methane. The samples were characterized by X‐ray diffraction, N2 adsorption, temperature‐programmed reduction, temperature‐programmed oxidation, scanning electron microscopy, and transmission electron microscopy. The catalysts showed high catalytic activity and good stability in the steam reforming of methane. Increasing the nickel loading up to 10 wt% gave increased activity. Catalysts with higher nickel loadings showed more deposited carbon after reaction. The excellent anti‐coking performance of the catalysts was attributed to the formation of a nickel‐magnesia solid solution, basicity of the support surface, and nickel‐support interaction.     

二氧化硫脲:一锅合成吡喃并[4,3-b] 吡喃类化合物的高效可重复使用有机催化剂（英文）

A series of pyrano[4,3‐b]pyran derivatives have been synthesized in excellent yields by the reaction of aromatic aldehydes with malononitrile or cyanoacetate and 4‐hydroxy‐6‐methylpyran‐2‐one in water at 80 °C, with the transformation being catalyzed by an aqueous solution of thiourea dioxide(TUD). Upon completion of the reaction, the product was isolated by filtration or extraction and the remaining aqueous TUD solution could be reused several times without any discernible impact on its catalytic activity. This procedure offers several advantages over existing procedures, including high yields, operational simplicity, the use of a non‐toxic catalyst and solvent, short reaction time and minimum pollution of the environment, making it a useful and attractive process for the preparation of pyrano[4,3‐b]pyran derivatives.     

碱性离子液体催化甘油合成1,2-甘油碳酸酯(英)

以离子液体为催化剂,在无溶剂体系中,考察了生物质平台化合物甘油转化1,2-甘油碳酸酯的反应.与酸性离子液体和常用无机碱性催化剂相比,碱性离子液体咪唑基1-丁基-3-甲基咪唑([Bmim]Im)、氢氧化1-丁基-3-甲基咪唑([Bmim]OH)、咪唑基1-烯丙基-3-甲基咪唑([Amim]Im)、氢氧化1-烯丙基-3-甲基咪唑([Amim]OH)在甘油与碳酸二甲酯的酯交换反应中表现出优异的活性.其中,以[Bmim]Im离子液体为催化剂时甘油转化率为98.4%和甘油碳酸酯选择性接近100%.另外,该离子液体可以回收重复利用3次后甘油转化率仍可达92%,甘油碳酸酯选择性可近100%.此碱性离子液体催化方法具有反应结果较好、产物分离简单、条件温和以及环境友好等特点.     

Glycolysis of poly(ethylene terephthalate) (PET) using basic ionic liquids as catalysts

The glycolysis of poly(ethylene terephthalate) (PET) was studied using several ionic liquids and basic ionic liquids as catalysts. The basic ionic liquid, 1-butyl-3-methylimidazolium hydroxyl ([Bmim]OH), exhibits higher catalytic activity for the glycolysis of PET, compared with 1-butyl-3-methylimidazolium bicarbonate ([Bmim]HCO₃), 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) and 1-butyl-3-methylimidazolium bromide ([Bmim]Br). FT-IR, ¹H NMR and DSC were used to confirm the main product of glycolysis was bis(2-hydroxyethyl) terephthalate (BHET) monomer. The influences of experimental parameters, such as the amount of catalyst, glycolysis time, reaction temperature, and dosages of ethylene glycol on the conversion of PET, yield of BHET were investigated. The results showed a strong influence of the mixture evolution of temperature and reaction time on depolymerization of PET. Under the optimum conditions of m(PET):m(EG): 1:10, dosage of [Bmim]OH at 0.1 g (5 wt%), reaction temperature 190 °C and time 2 h, the conversion of PET and the yield of BHET were 100% and 71.2% respectively. Balance between the polymerization of BHET and depolymerization of PET could be changed when the reaction time was more than 2 h and contents of catalyst and EG were changed.     

[Bmim]PF6 and BF4 ionic liquids as novel and recyclable reaction media for aromatic amination

Activated aryl halides undergo smooth nucleophilic substitution reactions with secondary amines in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF₆) or 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF₄) ionic liquids (ILs) at room temperature to afford the corresponding arylamines in excellent yields under mild and neutral conditions.     

[Bmim]BF4 ionic liquid: a novel reaction medium for the synthesis of β-amino alcohols

Epoxides undergo smooth ring-opening with aryl amines in 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF₄) or 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF₆) ionic liquids under mild and neutral conditions to afford the corresponding β-amino alcohols in excellent yields with high regioselectivity.     

离子液体型表面活性剂研究

以1-甲基咪唑为原料, 制备了6个常规离子液体: 1-正丁基-3-甲基咪唑四氟硼酸盐及六氟磷酸盐(简称[bmim][BF₄]及[bmim][PF₆])、1-正己基-3-甲基咪唑四氟硼酸盐及六氟磷酸盐(简称[hmim][BF₄]及[hmim][PF₆])、1-正十六烷基-3-甲基咪唑四氟硼酸盐及六氟磷酸盐(简称[C₁₆mim][BF₄]及[C₁₆mim][PF₆])和4个功能化离子液体: 1-(2-羟乙基)-3-甲基咪唑四氟硼酸盐及六氟磷酸盐(简称[2-hemim][BF₄]及[2-hemim][PF₆])、1-乙氧羰基甲基-3-甲基咪唑四氟硼酸盐及六氟磷酸盐(简称[eocmmim][BF₄]及[eocmmim][PF₆]). 研究了这两类离子液体的一些物理性能, 旨在挖掘离子液体在香料香精化妆品工业中的应用价值. 分别检测了它们与一般溶剂的互溶性, 并测定了它们的表面张力和发泡性能, 实验结果表明, 仅[C₁₆mim][BF₄]和[C₁₆mim][PF₆]具有发泡性能, 发泡力分别为68和120 mm.     

Theoretical study on cation-anion interaction and vibrational spectra of 1-allyl-3-methylimidazolium-based ionic liquids

In order to deepen the understanding of the cation-anion interaction in ionic liquids, the structures of cation, anions, and cation-anion ion-pairs of 1-allyl-3-methylimidazolium-based ionic liquids are optimized using density functional theory (DFT), and their most stable geometries are discussed. The structural parameters, hydrogen bonds and interaction energies of 1-allyl-3-methylimidazolium dicyanamide ([Amim]DCA), 1-allyl-3-methylimidazolium chloride ([Amim]Cl), 1-allyl-3-methylimidazolium formate ([Amim]FmO) and 1-allyl-3-methylimidazolium acetate ([Amim]AcO) ion pairs are studied. The vibrational frequencies of [Amim]DCA and [Amim]Cl have been calculated and scaled values have been compared with experimental FT-IR and FT-Raman spectra. The complete assignments were performed on the basis of the potential energy distribution (PED) of the vibrational modes.     

Isobaric vapor–liquid equilibria for ethanol–water system containing different ionic liquids at atmospheric pressure

Isobaric vapor–liquid equilibrium (VLE) data for ethanol–water systems containing ionic liquids (ILs) 1-methyl-3-methylimidazolium dimethylphosphate ([MMIM][DMP]), 1-ethyl-3-methylimidazolium diethylphosphate ([EMIM][DEP]), 1-butyl-3-methylimidazolium bromide ([BMIM][Br]), 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]) and 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF₆]) at atmospheric pressure (101.32 kPa) were measured with a circulation still. The results showed that the VLE of ethanol–water systems in the presence of different ILs was obviously different from that of the IL-free system. All ILs studied showed a salting-out effect, which gave rise to a change of the relative volatility of ethanol, and even to an elimination of the azeotropic point. It was found that the salting-out effect followed the order of [BMIM][Cl] > [BMIM][Br] > [BMIM][PF₆] and [MMIM][DMP] > [EMIM][DEP], which was ascribed to the preferential solvation ability of the ions resulting from the dissociation of the IL.     

The physicochemical properties of some imidazolium-based ionic liquids and their binary mixtures

The density, viscosity and conductivity of ionic liquids (ILs), 1-octyl-3-methylimidazolium tetrafluoroborate ([omim][BF4]), 1-octyl-3-methylimidazolium chloride ([omim][Cl]), 1-hexyl-3-methylimidazolium tetrafluoroborate ([hmim] BF4]), 1-hexyl- 3-methylimidazolium chloride ([hmim][Cl]), 1-hexyl-3-methylimidazolium hexafluorophosphate ([hmim][PF6]), and the [omim][BF4] + [omim][Cl], [hmim][BF4] + [hmim][Cl], and [hmim][PF6] + [hmim][Cl] binary mixtures were studied at dif- ferent temperatures. It was demonstrated that the densities of both the neat ILs and their mixtures varied linearly with temper- ature. The density sensitivity of a binary mixture is between those of the two components. The excess molar volumes (VE) of [hmim][BF4] + [hmim][Cl] and [hmim][PF6] + [hmim][Cl] mixtures are positive in the whole composition range. For [omim][BF4] + [omim][Cl], the VE is also positive in the [omim][Cl]-rich region, but is negative in the [omim][BF4]-rich re- gion. The viscosity or conductivity of a mixture is in the intermediate of those of the two neat ILs. For all the neat ILs and the binary mixtures studied, the order of conductivity is opposite to that of the viscosity. The Vogel-Tammann-Fulcher (VTF) equations can be used to fit the viscosity and conductivity of all the neat ILs and the binary mixtures. The neat ILs and their mixtures obey the Fractional Walden Rule very well, and the values of the Walden slopes are all smaller than unit, indicating obvious ion associations in the neat ILs and the binary mixtures.     

Ionic Liquid-Induced Structural and Activity Changes in Hen Egg White Lysozyme

Lysozyme crystals in the presence of 1-butyl-3-methylimidazolium tetrafluoroborate ([C₄mim]BF₄), 1-butyl-3-methylimidazolium chloride ([C₄mim]Cl), 1-butyl-3-methylimidazolium bromide([C₄mim]Br), and 1,3-dimethylimidazolium iodine([dmim]I) were prepared, and the influence of ionic liquids (ILs) on the structure and activity change of lysozyme was investigated. Fourier transform infrared spectroscopy revealed the major secondary structures of α-helix and β-sheet for lysozyme. It was interesting to note that increases of the band near 2,935 and 1,656 cm^?1 from Raman spectroscopy are attributed to the unfolding of lysozyme molecules. A shift in amide III from 1,230 to 1,270 cm^?1 in adding [dmim]I occurs, indicating a transformation from β-sheet to random coil. With regard to adding [C₄mim]BF₄, [C₄mim]Cl, and [C₄mim]Br, α-helix and β-sheet are the predominant structures for lysozyme. The activity study showed that the ILs used brought a positive effect. Especially, [dmim]I leads to a drastic increase in relative activity, and its value reaches 50 %.     

吡咯烷酮酸性离子液体中硼酸酯的催化合成

研究了硼酸与频哪醇和环己醇在离子液体1-甲基-2-吡咯烷酮硫酸氢盐（[Hnmp]HSO4）、1-丁基-3-甲基咪唑四氟硼酸盐（[Bmim]BF4）及1-丁基-3-甲基咪唑六氟磷酸盐([Bmim]PF6)中生成2-环己氧基-4,4,5,5-四甲基-1,3,2-二氧硼烷的酯化反应。 考察了不同离子液体、反应温度、反应时间和离子液体与反应物物质的量比等对反应的影响。 结果表明,当n(硼酸)∶n(频哪醇)∶n(环己醇)∶n([Hnmp]HSO4)=1∶1∶1∶1,反应温度为70 ℃和反应时间为4 h时,硼酸酯的产率为72.5%,离子液体重复使用4次,催化活性无明显降低。