Synthesis and properties of a star-shaped organic material with triphenylamine and N-vinyl carbazole units

A starburst triphenylamine cored N-vinyl carbazole (V-Cz) branched compound was designed and synthesized via optimized Heck reaction in a yield of 40-60%.Moderate yield came from decomposition of V-Cz and self-coupling of triiodo-triphenylamine. TCz-TPA adopts a highly twisted propeller conformation by molecular mechanical optimization.It is readily soluble for its highly twisted conformation.Transparent and pinhole free films could be easily fabricated by spin-coating for its starburst structure.It emits blue-greenish light in CH_2Cl_2 peaked at 460 nm with a narrow full-width at half-maximum (FWHM) of 65 nm.As compared, the absorption peaks of the spin-coated film blue shifted and emission peak red shifted to 510 nm with a FWHM of 96 nm.     

Heck Reaction of Iodoarenes with Methyl Acrylate Catalyzed by Cyciopalladated Complexes of Tertiary Arylamines Immobilized in Ionic Liquid[ Bmim ] ^＋ BF4^-

Heck reaction of iodoarenes with methyl acrylate, catalyzed by cyclolmlladated complexes of tertiary arylamines, was investi-gated in ionic liquid 1-butyl-3-metylimidazolium tetratluorobo-rate ([Bmim] BF4^- ). The products can be isolated convenient-ly from the ionic liquid-catalyst system. The catalysts could be reused for more than 10 times still with satisfactory catalytic ac-tivity.     

Chitosan-immobilized Palladium Complex：a Green and Highly Active Heterogeneous Catalyst for Heck Reaction

A green heterogeneous catalyst for Heck reaction-chitosan-immobilized palladium complex was prepared.The catalyst exhibits high activity and stereoselectivity under the moderate reaction conditions.The catalyst can be separated easily from the reaction mixture and reused after washing.Under the suitable reaction conditions,the cross-coupling of iodobenzene (ArI) with acrylic acid (AA) or acrylate can be achieved 93.3% or 99% yield of trans-cinnarnic acid or trans-cinnamic ester.     

Synthesis and characterization of silica-supported Pd nanoparticles and its application in the Heck reaction

Well-dispersed palladium nanoparticles immobilized onto modified silica(SiO 2-pr-NH-cyanuric-SH) have been prepared in some facile steps.The catalyst exhibits high catalytic activity in the Heck reaction,and can be easily recovered and reused without significant loss of its activity in several runs.     

Preparation and application of SBA-15-supported palladium catalyst for Heck reaction in supercritical carbon dioxide

A new method for the preparation of SBA-15-supported palladium catalyst for Heck reaction in supercritical carbon dioxide was presented.The newly formed SBA-15-supported palladium catalyst（Ph-SBA-15-PPh₃-Pd） exhibited high catalytic activity for the Heck reaction of 4-nitrobromobenzene with methyl acrylate.The catalyst can be reused several times without a loss of activity.     

Nanosized Pd assembled on superparamagnetic core–shell microspheres:Synthesis,characterization and recyclable catalytic properties for the Heck reaction

A series of magnetically recyclable Pd/Fe3O4@g-Al2O3 catalysts were synthesized using the superparamagnetic Fe3O4@g-Al2O3core–shell microspheres as the supporter and nano-Pd particles assembled on g-Al2O3 shell as the active catalytic component.The structure of the catalysts was characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),N2adsorption–desorption and vibrating sample magnetometer(VSM).The catalytic activity and the recyclability properties of the catalysts for the Heck coupling reaction with aryl bromides and the olefins were investigated.The results show that the microspheres of the magnetic Pd/Fe3O4@g-Al2O3 catalysts were about 400 nm and the nano-Pd particles assembled on g-Al2O3 shell were about 3–4 nm in size.The saturation magnetization(MS) of the magnetic catalysts was sufficiently high to allow magnetic separations.In the Heck coupling reactions,the magnetic Pd/Fe3O4@g-Al2O3 catalysts exhibited good catalytic activity and recyclability.With Pd/Fe3O4@g-Al2O3(0.021 mol%) catalyst,the bromobenzene conversion and product yield reached about 96.8% and 91.2%,respectively,at 120 8C and in 14 h.After being recycled for six times,the conversion of bromobenzene and the recovery of the catalyst were about80% and 90%,respectively.The nano-Pd particles were kept well dispersed in the used Pd/Fe3O4@g-Al2O3 catalysts.     

Synthesis of 3-Benzyloxy-6-methyl-7-methoxyphenanthrene-9-carboxaldehyde with Utilize Intramolecular Heck Reaction as the Key Step

The substituted phenanthrene-9-carboxyaldehydes are very important intermediates for the syntheses of phenanthroindolizidine and phenanthroquinolizidine alkaloids. The novel title compound was prepared from the reaction of 5 steps starting from the condensation of 3-methoxyl-4-methyl-phenylacetic acid and 4-（benzyloxy）-2-iodobenzaldehyde, followed by esterification, cyclization, reduction, and oxidation. A new method for the preparation of phenanthrene ring via palladium-catalyzed intramolecular Heck reaction was described. The title compound was characterized by IR, ^1H NMR, ^13C NMR, elemental analysis, and MS.     

三(羟甲基)氨基甲烷改性SiO_2固载钯纳米粒子:合成、表征及其催化Heck偶联反应活性（英文）

The preparation of supported Pd nanoparticles on Tris(tris(hydroxymethyl)aminomethane)‐ modi‐fied Si O2 gel and their catalytic application in Heck coupling are investigated. The catalyst was char‐acterized using a combination of X‐ray diffraction, transmission electron microscopy, field‐emission scanning electron microscopy, and scanning electron microscopy/energy‐dispersive X‐ray spec‐troscopy. The supported Pd nanoparticles were found to be a highly active and reusable catalyst for the Heck reaction at a low Pd loading(0.02 mol%) because of stabilization by the Tris moieties. Several reaction parameters, including the type and amount of solvent, base, and temperature, were evaluated. The heterogeneity of the catalytic system was investigated using different approaches, and showed that slight Pd leaching into the reaction solution occurred under the reaction condi‐tions. Despite this metal leaching, the catalyst can be reused seven times without significant loss of its activity.     

Magnetically recyclable Pd/γ-AlOOH@Fe_3O_4 catalysts and their catalytic performance for the Heck coupling reaction

Novel magnetically recyclable Pd/γ-AlOOH@Fe3O4 catalysts were prepared using γ-AlOOH@Fe3O4 as a magnetic supporter and nano-Pd particles as the active catalytic component.The structure of the catalysts was characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),N2 adsorption-desorption,and a vibration sample magnetometer(VSM).The catalytic activity and recyclability for the Heck coupling reaction were investigated.Results showed that the magnetic γ-AlOOH@Fe3O4 possessed a core-shell structure,as well as that the nano-Pd particles were 6–8 nm and had been well dispersed in the γ-AlOOH shell.In the Heck coupling reactions,the magnetic Pd/γ-AlOOH@Fe3O4 catalysts exhibited good catalytic activity and recyclability.For the(0.021 mol%)Pd/γ-AlOOH@Fe3O4 catalyst,the bromobenzene conversion and product yield reached about 100%and 96.3%,respectively,under a 120°C reaction temperature and 12 h reaction time.After being recycled 8 times,the conversion of bromobenzene and the recovery of the catalyst were about 90%and 93%,respectively.The nano-Pd particles were kept well dispersed in the used Pd/γ-AlOOH@Fe3O4 catalyst.     

Investigation on the Coordination Mode of IL-Supported Diols Used as Phosphine-Free Ligands for Palladium Catalyzed Heck Reaction

The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported diols with metal Pd in Heck reaction was related to the changes of the cation rings, leading to the different activities of Pd catalyst in the reaction. The experimental results indicated that the activities of Pd catalyst were affected mainly by n-electron density of the cation rings. Compared to pyridinium and piperidinium cations, imidazolium cations showed the best coordination to metal Pd. In the meantime, C-2 hydrogen and the length of alkyl side chains had impacts on the coordination as well.     

磁性离子液体的应用研究

磁性离子液体是指能够吸附在磁铁上,在外加磁场作用下具有一定磁化强度的离子液体。本文综述了自2004年磁性离子液体概念提出至今在各领域的应用,其可以催化吡咯、3-甲基噻吩等单体合成导电高分子纳米微球,同时起到溶剂和模板的作用;还可以通过外加磁场调整产物的微观结构和形貌,从而得到不同的纳米结构;它也可以充当Lewis酸催化剂,催化傅克反应等一系列化学反应,并可以回收重复使用,而且回收有望通过磁场简单实现;与碳纳米管以共价键结合可以制备具有磁性的碳纳米管。除此之外,磁性离子液体在光控顺磁性超分子体系、吸收有机挥发物等领域的应用在近年也陆续有报道。     

Design of guanidinium ionic liquid based microwave‐assisted extraction for the efficient extraction of Praeruptorin A from Radix peucedani

A series of novel tetramethylguanidinium ionic liquids and hexaalkylguanidinium ionic liquids have been synthesized based on 1,1,3,3‐tetramethylguanidine. The structures of the ionic liquids were confirmed by ¹H NMR spectroscopy and mass spectrometry. A green guanidinium ionic liquid based microwave‐assisted extraction method has been developed with these guanidinium ionic liquids for the effective extraction of Praeruptorin A from Radix peucedani. After extraction, reversed‐phase high‐performance liquid chromatography with UV detection was employed for the analysis of Praeruptorin A. Several significant operating parameters were systematically optimized by single‐factor and L₉ (3⁴) orthogonal array experiments. The amount of Praeruptorin A extracted by [1,1,3,3‐tetramethylguanidine]CH₂CH(OH)COOH is the highest, reaching 11.05 ± 0.13 mg/g. Guanidinium ionic liquid based microwave‐assisted extraction presents unique advantages in Praeruptorin A extraction compared with guanidinium ionic liquid based maceration extraction, guanidinium ionic liquid based heat reflux extraction and guanidinium ionic liquid based ultrasound‐assisted extraction. The precision, stability, and repeatability of the process were investigated. The mechanisms of guanidinium ionic liquid based microwave‐assisted extraction were researched by scanning electron microscopy and IR spectroscopy. All the results show that guanidinium ionic liquid based microwave‐assisted extraction has a huge potential in the extraction of bioactive compounds from complex samples.     

PEG型酸性温控离子液体中芳香酸和醇的酯化反应

报道了该催化体系在芳香酸和醇酯化反应中的应用. 研究发现, 该离子液体具有优良的催化性能, 产品易分离, 催化剂可循环使用且活性不降低, 催化剂不易流失, 实现了均相催化剂的高效回收和再利用.     

离子液体催化制备5-羟甲基糠醛的研究进展

本文综述了离子液体催化制备5-羟甲基糠醛的研究进展。运用离子液体作为反应溶剂和催化剂,与常规合成HMF的方法相比,其反应在常压、低温下进行,更易于操作控制;副反应数量明显减少,HMF的产率稳定,可达90%;离子液体催化活性稳定,可重复利用,减少了有机溶剂的使用量;利用离子液体作为媒介,能将反应原料从单一的果糖扩展到葡萄糖和纤维素等廉价原料,降低了生产成本。由此可见,运用离子液体催化制备HMF将是今后研究的重点和发展的必然趋势。     

过渡金属离子液体EMIFeCl3的性质研究

在干燥高纯氩气氛的手套箱内, 直接将摩尔比为1∶1的高纯无水FeCl3与氯化1-甲基-3-乙基咪唑(EMIC)混合, 得到棕色透明的离子液体EMIFeCl4. 在293.15~343.15 K温度范围内测定了该离子液体的密度和表面张力. 利用Glasser经验方程和空隙模型研究了EMIFeCl4的性质, 并与离子液体EMIAlCl4进行比较, 指出空隙模型具有一定的合理性.     

Incorporation of ionic liquid into porous polymer monoliths to enhance the separation of small molecules in reversed‐phase high‐performance liquid chromatography

An ionic liquid was incorporated into the porous polymer monoliths to afford stationary phases with enhanced chromatographic performance for small molecules in reversed‐phase high‐performance liquid chromatography. The effect of the ionic liquid in the polymerization mixture on the performance of the monoliths was studied in detail. While monoliths without ionic liquid exhibited poor resolution and low efficiency, the addition of ionic liquid to the polymerization mixture provides highly increased resolution and high efficiency. The chromatographic performances of the monoliths were demonstrated by the separations of various small molecules including aromatic hydrocarbons, isomers, and homologues using a binary polar mobile phase. The present column efficiency reached 27 000 plates/m, which showed that the ionic liquid monoliths are alternative stationary phases in the separation of small molecules by high‐performance liquid chromatography     

Preparation of magnetic chitosan and graphene oxide-functional guanidinium ionic liquid composite for the solid-phase extraction of protein

A series of novel cationic functional hexaalkylguanidinium ionic liquids and anionic functional tetraalkylguanidinium ionic liquids have been synthesized, and then magnetic chitosan graphene oxide (MCGO) composite has been prepared and coated with these functional guanidinium ionic liquids to extract protein by magnetic solid-phase extraction. MCGO-functional guanidinium ionic liquid has been characterized by vibrating sample magnetometer, field emission scanning electron microscopy, X-ray diffraction spectrometer and Fourier transform infrared spectrometer. After extraction, the concentrations of protein were determined by measuring the absorbance at 278 nm using an ultra violet visible spectrophotometer. The advantages of MCGO-functional guanidinium ionic liquid in protein extraction were compared with magnetic chitosan, graphene oxide, MCGO and MCGO-ordinary imidazolium ionic liquid. The proposed method has been applied to extract trypsin, lysozyme, ovalbumin and bovine serum albumin. A comprehensive study of the adsorption conditions such as the concentration of protein, the amount of MCGO-functional guanidinium ionic liquid, the pH, the temperature and the extraction time were also presented. Moreover, the MCGO-functional guanidinium ionic liquid can be easily regenerated, and the extraction capacity was about 94% of the initial one after being used three times.     

固定化离子液体在有机合成中的应用

固定化离子液体是将离子液体通过物理吸附或化学键合等方法与固载材料结合而成,不仅保持了离子液体稳定性好、挥发性低、结构可优化等特点,还提高了离子液体的催化活性和重复利用性。固定化离子液体广泛应用于缩合、偶联及不对称合成等反应中。本文介绍了固定化离子液体的制备、固载材料的分类、结合方式及固定化离子液体在有机合成中的应用进展。     

Immobilization of Pd(II) Catalysts for Cyclopropanation in Ionic Liquid

Ｈｏｍｏｇｅｎｅｏｕｓｃａｔａｌｙｓｉｓｏｆｆｅｒｓｍａｎｙａｄｖａｎｔａｇｅｓｏｖｅｒｈｅｔｅｒｏｇｅｎｏｕｓｃａｔａｌｙｓｉｓｗｉｔｈｒｅｓｐｅｃｔｔｏａｃｔｉｖｉｔｙ ,ｓｅｌｅｃｔｉｖｉ ｔｙ ,ｆｌｅｘｉｂｉｌｉｔｙｏｆｏｐｅｒａｔｉｏｎ .Ｈｏｗｅｖｅｒ ,ｔｈｅｃｏｎｔｉｎｕｏｕｓｃａｔ ａｌｙｓｔｃｏｎｓｕｍｐｔｉｏｎ ,ｃａｔａｌｙｓｔｒｅｍｏｖａｌｆｒｏｍｔｈｅｐｒｏｄｕｃｔｓａｎｄｃａｔａｌｙｓｔｄｉｓｐｏｓａｌｈａｖｅｓｔｉｌｌｔｏｂｅｉｍｐｒｏｖｅｄ .Ａｎａｔ ｔｒａｃｔｉｖｅａｐ…     

离子液体支撑液膜分离CO2

支撑液膜是一种在湿法冶金、生物技术以及气体分离等多个领域都有应用的重要膜分离技术。本文回顾了支撑液膜技术分离CO2的研究进展,按照液膜相的不同,分类介绍了常规载体支撑液膜和离子液体支撑液膜,指出了常规载体支撑液膜分离CO2的局限性,重点介绍了离子液体支撑液膜分离CO2的发展,分析了气体在离子液体支撑液膜中的传质机理以及常规离子液体结构、含量和支撑膜材料等对分离效果的影响;讨论了离子液体的功能化方法以及功能化离子液体支撑液膜分离CO2的渗透率、选择性和液膜稳定性;介绍了两种新的离子液体支撑液膜改进方法:聚离子液体膜与凝胶化离子液体支撑液膜。最后指出了今后用于CO2分离的离子液体支撑液膜的发展方向。