新型室温离子液体六烷基胍盐的制备及性质

近年来 ,离子液体 (IL)作为“绿色”溶剂受到学术和工业界的关注 .英国 BP公司和法国的 IFP等研究机构从 2 0世纪 80年代起就开始探索离子液体作为溶剂与催化剂的可能性 ,至今在离子液体体系中已实现了许多催化反应 [1～ 5] .室温离子液体 (RTIL S)是指在常温下呈液态的熔盐体系 .通常由烷基吡啶或双烷基咪唑季铵阳离子与氯铝酸根、氟硼酸根及氟磷酸根等阴离子组成 .在季铵盐类离子液体中 ,咪唑盐的合成和应用研究尤为突出 .目前 ,对于既可作为溶剂又可作为催化剂的室温离子液体的合成和应用已成为研究热点 [6 ] ,如室温离子液体 [EMI…     

离子液体的量化计算及分子动力学模拟研究进展

离子液体是由有机阳离子和无机/有机阴离子构成的盐类,一般在室温或接近于室温下呈液态,因此常被称为室温离子液体(RTIL).依据不同的划分标准,离子液体有多种分类方式:根据年代的不同可将离子液体分为第一代、第二代及第三代离子液体,例如:烷基咪唑和烷基吡啶的金属卤化物盐等[1];根据阳离子的不同可将离子液体分为季鏻     

手性胍盐离子液体的合成

离子液体作溶剂、催化剂进行有机合成反应是近几年来各国化学家关注的热点之一[1].究其原因主要是离子液体具有低熔点、不挥发、不易燃易爆等特点,使其能代替传统有机合成与工业催化工程中的易挥发性溶剂(VOCs).再就是离子液体作为一种离子溶剂,可能存在1018种二元离子液体,而现在实际应用中的分子溶剂大概600种,离子液体的多样性使得在实际应用中可以通过调节离子液体的结构来调节离子液体的性质,从而为反应提供合适的溶剂环境,从而提高反应的产率、选择性以及立体选择性等[2].手性离子液体的合成和离子液体中的不对称催化一直都是离子液体研究的一个重要方面.Wasserscheid等[3,4]最近报道了从"手性池"(Chiral pool)衍生的新手性离子液体的合成和特性.最近我们报道一类简单的胍盐室温离子液体的合成及性质[5,6],新型胍盐离子液体由于其独特的性质得到了大家的关注[7-8].而手性胍盐离子液体还未见文献报道,因此我们从简单易得的手性胺出发合成了一系列的手性胍盐离子液体(Scheme 1),以新的手性胍盐离子液体作为不对称性催化反应新体系的工作正在进行.     

离子液体及其在分离分析中的应用进展

室温离子液体是一类熔点在室温附近的熔融盐，以其熔点低、蒸汽压小、电化学窗口宽、酸性可调节以及良好的溶解性等特点在电化学、有机合成、催化、分离等领域应用广泛。综述了离子液体在分离分析上的应用进展。参考文献48篇。     

甲基咪唑甲酸盐离子液体中MMA的原子转移自由基聚合

离子液体（Ils）是完全由正负离子组成且常温下呈液态的有机盐.离子液体几乎没有可测量的蒸汽压,具有不可燃,热容量大,热稳定性好等优点,并且对有机物,无机物,金属有机物,聚酯等均有很好的溶解能力,近几年来,在各种化学反应中,作为“绿色溶剂”使用的室温离子液体由于其独特的性质受到了越来越多的重视。     

疏水性咪唑类混合离子液体的物理化学性质

本文选取疏水性和疏水性离子液体混合物作为研究对象, 将疏水性离子液体1-甲基-3-n-丁基咪唑三氟甲基磺酰胺盐[BMImN(CF3SO2)2]与BMImPF6以不同的比例进行混合, 对混合离子液体及其相应单组分离子液体进行了相关物理化学性质的测试和对比, 讨论由于混合导致的物理化学效应.     

室温离子液体在过渡金属催化反应中的应用研究进展

室温离子液体(RTILs)是在室温或近于室温下呈液态的由离子构成的盐类．如图1所示，RTILs按阳离子类型可以分为4类：烷基季铵盐离子；烷基季鳞盐离子；N，N-二烷基咪唑离子和N-烷基吡啶离子．按阴离子可分为：氯化盐 AlX3(X=卤素)和含有RF1^-,PF6^-等阴离子的离子液体．     

离子液体的制备与性质表征——介绍一个综合化学实验

本实验以甲基咪唑为原料,合成1－甲基－3－丁基咪唑溴盐,再通过阴离子交换合成1－甲基－3－丁基咪唑氟硼酸盐和1－甲基－3－丁基氟磷酸盐离子液体,然后通过红外、紫外、核磁对其进行表征。并测定了上述离子液体的电导率、黏度、吸水性和溶解性等性质。     

离子液体的周期性变化规律及导向图

离子液体是完全由阴阳离子组成的室温下呈液态的盐类, 其作为绿色溶剂近年来成为众多领域的研究热点. 由于阴阳离子种类繁多, 阴阳离子的不同组合而形成的离子液体种类理论上几乎是无限的. 而在庞大的离子液体家族中如何选择合适的离子液体或者如何设计新型的功能离子液体成为离子液体研究及其应用的瓶颈. 门捷列夫的元素周期律启发我们在离子液体中寻找与之类似的规律. 本文正是基于这样一个思路, 试图建立离子液体周期率和离子液体导向图, 从而为寻找和设计离子液体提供明确的方向. 如果最终能够建立起一套完整的离子液体各种性质的周期律, 将会从本质上理解离子间及分子片间的性质差异与相互作用.     

LiCl-Urea两元体系离子液体的研究

自从1914年第一种离子液体[EtNH3]NO3问世以来,室温离子液体的研究与应用取得了飞速的发展,离子液体以其诸多的优良性能,在催化、有机反应、萃取、以及气相色谱、电化学中得到了广泛地应用。近几年来,多元离子液体体系的研究受到关注。本文报导了由LiCl简单盐和Urea形成的二元体系离子液体,最低共熔点为55℃(LiCl的熔点是608℃,尿素本身的熔点是132℃)。     

Ionische Flüssigkeiten: Innovative Lösungsmittel für die Zweiphasenkatalyse

Ionic liquids are low melting salts which represent a new class of non-molecular, ionic solvents. By combining different cations and anions a large number of liquids with very different physical and chemical properties can be obtained. It is possible to optimize the ionic medium for a specific application by the careful choice of the ion combination. Ionic liquids are interesting substitutes for organic solvent in catalytic reactions for many reasons: Besides their non-volatile nature offering significant engineering advantages, the unusual solubility properties of these liquids enable new multiphasic catalytic reactions.     

Tetraalkylphosphonium-based ionic liquids

Ionic liquids are salts that are liquid at or near room temperature. Their wide liquid range, good thermal stability, and very low vapor pressure make them attractive for numerous applications. The general approach to creating ionic liquids is to employ a large, unreactive, low symmetry cation with and an anion that largely controls the physical and chemical properties. The most common cations used in ionic liquids are N-alkylpyridinium and N,N′-dialkylimidazolium. Another very effective cation for the creation of ionic liquids is tetraalkylphosphonium, [PR₁R₂R₃R₄]⁺. The alkyl groups, R_n, generally are large and not all the same. The halide salts of several phosphonium cations are available as starting materials for metathesis reactions used to prepare ionic liquids. The large phosphonium cations can combine with relatively large anions to make viscous but free flowing liquids with formula mass greater than 1000 g mol⁻¹. Some other more massive salts are waxes and glasses. The synthesis and the physical, chemical, and optical properties of phosphonium-ionic liquids having anions with a wide range of masses were measured and are reported here.     

离子液体固定化材料在固相萃取中的应用研究进展

离子液体是由阴、阳离子组成的低温熔融盐,几乎没有蒸汽压,具有稳定性好、溶解能力强、结构可设计、导电性好等优良性能。离子液体作为一种广受关注的新型“绿色溶剂”,具有代替传统有机溶剂的潜力,其制备方法和应用范围研究日趋完善和多样,已广泛应用于催化化学、光电化学、材料化学和分析化学等领域。离子液体通过功能化导向设计后,可以将羟基、氨基、羧基、氰基等活性基团键合在离子液体结构上,促使其更加易于与目标分子通过生成π-π键、氢键、离子键和范德华力等而产生相互作用,更加易于发生固定化反应。将离子液体负载到固体载体材料进行固定化后,新型材料既可以减少离子液体的流失,同时保留了离子液体和固体载体的独特性能,具有富集效率高、吸附容量高、稳定性好、识别位点多、萃取选择性强、离子液体利用率高等特点,近年来,在有机小分子固相萃取分离研究中应用广泛。该文从离子液体与硅胶、分子筛、分子印迹聚合物、氧化石墨烯、磁性材料等固体载体的固定化研究情况入手,综述了离子液体固定化材料在固相萃取分离中的应用情况,涉及的目标分离物质包括生物碱类、黄酮类、多酚类等天然活性成分,以及常见药物分子、有机农药等有机小分子化合物,系统地介绍了离子液体与多种载体固定化的性质、应用和分离机制。离子液体的引入,增加了复合材料的活性位点分布和吸附容量,离子液体固定化材料的吸附效率与离子液体种类、吸附材料用量、样品溶液浓度、吸附温度、pH值、洗脱溶剂类型、用量及流速等因素有关。该文探讨了离子液体结构相对单一、相关基础理论研究相对薄弱、复杂基质萃取程度不理想等问题,并提出相应的解决思路,以期为离子液体固定化材料在复杂基质中目标分子分离分析方面的应用提供借鉴和参考。     

离子液体参与构筑的微乳液:离子液微乳液

微乳液一般是指两种互不相溶的液体(极性相:一般为水;非极性相:一般为有机溶剂),在表面活性剂作用下形成的均一透明的热力学稳定体系,已广泛应用于材料制备、化学合成等领域.离子液体是熔点低于100℃,完全由离子组成的一类物质,作为一种"绿色溶剂",具有诸多优异的物理化学性质,又被称为"可设计型溶剂".本文综述了离子液体作为极性相、非极性相,甚至表面活性剂,构筑的一类微乳液――离子液微乳液,重点介绍了其物理化学性质的研究进展,并展望了发展趋势.     

Ionic Liquids as Mobile Phase Additives for Separation of Nucleotides in High-Performance Liquid Chromatography

Ionic liquids are a type of salts that are liquid at low temperature (＜100℃). Because of their some special properties, they have been widely used as new “green solvents” for many chemical reactions and liquid-liquid extraction in the past several years. In this paper, a new method for the separation of nucleotides is developed and the essential feature of the method is that 1-alkyl-3-methylimidazolium salts are used as mobile phase additives, resulting in a baseline separation of nucleotides without need of gradient elution and need of organic solvent addition as currently used in RP-HPLC. This study shows the potential application of ionic liquids as mobile phase additives in reversed-phase liquid chromatograohy.     

离子液体在自由基聚合反应中的应用研究进展

室温离子液体是完全由离子构成的液体,具有几乎没有蒸汽压、溶解度大、溶解范围广、易于回收利用、稳定性好等特点,广泛应用于电化学、有机反应、分离萃取、复合材料等各个领域。近年来已成为各种聚合反应研究的重要课题,且主要集中于自由基聚合反应。作为聚合反应的溶剂,离子液体对聚合反应速率、分子量、聚合物的结构性能都有一定影响。本文根据近几年的文献,归纳分析了离子液体中的常规自由基聚合和活性自由基聚合的反应动力学、反应机理、聚合产物的结构和性能以及离子液体的回收利用等问题。     

Towards large-scale, fully ab initio calculations of ionic liquids

Ionic liquids have attracted a substantial amount of interest as replacement of traditional electrolytes in high efficiency electrochemical devices for generation and storage of energy due to their superior physical and chemical properties, especially low volatility and high electrochemical stability. For enhanced performance of the electrochemical devices ionic liquids are required to be highly conductive and low viscous. Long-range Coulomb and short-range dispersion interactions between ions affect physical and chemical properties of ionic liquids in a very complex way, thus preventing direct correlations to the chemical structure. Considering a vast combination of available cations and anions that can be used to synthesize ionic liquids, development of predictive theoretical approaches that allow for accurate tailoring of their physical properties has become crucial to further enhance the performance of electrochemical devices such as lithium batteries, fuel and solar cells. This perspective article gives a thorough overview of current theoretical approaches applied for studying thermodynamic (melting point and enthalpy of vapourisation) and transport (conductivity and viscosity) properties of ionic liquids, emphasizing their reliability and limitations. Strategies for improving predictive power and versatility of existing theoretical approaches are also outlined.     

New ionic liquids with tris(perfluoroalkyl)trifluorophosphate (FAP) anions

The synthesis of new ionic liquids with tris(perfluoroalkyl)trifluorophosphate (FAP) anions is described. The physico-chemical properties (conductivity, viscosity, electrochemical and thermal stability) of this new generation of ionic liquids (molten salts) are discussed. FAP-ionic liquids show an excellent hydrolytic stability, low viscosity and high electrochemical and thermal stability that makes them attractive for use in electrochemical devices and as a new media for application in modern technologies and chemical synthesis.     

Ionic Liquids-New "Solutions" for Transition Metal Catalysis

Ionic liquids are salts that are liquid at low temperature (<100 degrees C) which represent a new class of solvents with nonmolecular, ionic character. Even though the first representative has been known since 1914, ionic liquids have only been investigated as solvents for transition metal catalysis in the past ten years. Publications to date show that replacing an organic solvent by an ionic liquid can lead to remarkable improvements in well-known processes. Ionic liquids form biphasic systems with many organic product mixtures. This gives rise to the possibility of a multiphase reaction procedure with easy isolation and recovery of homogeneous catalysts. In addition, ionic liquids have practically no vapor pressure which facilitates product separation by distillation. There are also indications that switching from a normal organic solvent to an ionic liquid can lead to novel and unusual chemical reactivity. This opens up a wide field for future investigations into this new class of solvents in catalytic applications.     

Ionic liquids with herbicidal anions

Ionic liquids with herbicidal anions (named herbicidal ionic liquids—HILs) were synthesized and characterized. The combination of two active chemicals as the [cation][anion] form in a single moiety reduced the number of additional chemicals required per application. HILs ([cation][MCPA]) exhibited higher biological activity than currently used salts of MCPA, and involved pesticides of a multidirectional activity ([plant growth regulator][MCPA]). Acute toxicity of HILs could be controlled by appropriate selection of cation type. These salts had chemical and thermal stability, and showed substantially lower water solubility than starting herbicides, thus reducing soil and groundwater mobility.