基于离子液体电解液的有机电化学反应

室温离子液体(RTILs) 作为一类在室温时呈液态且具有良好导电性的新型绿色溶剂, 在有机电化学反应体系中的应用前景广阔。本文介绍了近年报道过的新型离子液体及离子液体电解液的特性,阐述了基于离子液体电解液的电化学实验方法,重点综述了离子液体中的各种有机电化学反应,包括电化学还原反应、CO₂在离子液体中的电化学固定、电化学氧化反应、烯烃的环氧化、选择性氟化反应、偶联反应、功能化有机硅氧烷的合成、电化学氟化脱硫反应、电化学聚合反应等,并展望了发展趋势。     

离子液体中2,4,6-三溴苯酚的电化学还原脱卤

<正>室温离子液体的许多独特的性质为其在化学分离、电化学传感器、电池等领域展示了广阔的应用前景[1-3]。室温离子液体作为有机反应介质,可以克服水溶液电化学窗口较窄的缺点,还可避免或减少造成二次污染的大量有机溶剂[4]。利用离子液体的导电性,可将电化学反应中的     

室温离子液体在聚合反应中的应用

室温离子液体作为一种环境友好的“绿色溶剂”,具有很多独特的物理化学性能,可以应用于自由基聚合、阳离子聚合、配位聚合、电化学聚合等反应体系。本文介绍了室温离子液体在上述反应中的应用。     

室温离子液体的研究进展

对室温离子液体的制备及性能的研究进展进行了评述。室温离子液体的阳离子多为有机含氮杂环阳离子，阴离子通常为体积较大的无机阴离子。室温离子液体用作溶剂，具有液态温度范围宽、溶解能力强、蒸气压低、粘度高、电化学窗口宽等特点，在有机合成、电化学、无机物溶液化学方面具有广阔的应用前景。     

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℃)。     

双硫腙分光光度法测定离子液体中Zn2+含量

离子液体是由带正电的离子和带负电的离子所构成的低熔点有机熔盐,在室温下一般呈液态状。室温离子液体(IL)以高导电性、宽的电化学窗口、较大的液态温度区间、广泛的溶解性和极低的蒸气压等奇特的物理化学性质,在电化学、萃取分离、有机合成等领域得到普遍应用[1-2]。在离子液     

氯铝酸室温离子液体系中HCl促进的苯的烷基化反应研究

研究了少量HCL调变的氯铝酸室温离子液体超强酸催化体系中，苯与碳-12烯以及氯甲烷的烷基化反应，对于前一反应，以溶有HCL的氯铝酸室温离子液体为催化剂与没有HCL的相比，反应的产物分布不同，而后一反应过程中有HCL生成，与纯ALCL3作催化剂相比，催化活性显著提高，实验结果还表明，生成的烷基化产物不溶于离子液体，因而易于分离，催化剂可以重复使用。     

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。     

室温离子液体电解液中尖晶石LiMn_2O_4的电化学性质

应用循环伏安、恒电流充放电和电化学阻抗技术研究了尖晶石L iMn2O4于室温离子液体电解液中的电化学性质.实验表明,以室温离子液体作电解液,L iMn2O4的首次放电容量可达108.2 mAh/g、循环效率高于90%,温度和电流密度显著影响电极的电化学性能.交流阻抗测定了L i+在电极/电解液相界面迁移的活化能,为55 kJ/mol.根据界面反应的高活化能解释了L iMn2O4在该离子液体电解液中低温性能和倍率充放电性能不佳的原因.     

在离子液体中电化学还原合成2-氨基苯甲醚

利用循环伏安法研究了2-硝基苯甲醚在离子液体中的电化学还原行为。以Cu为工作电极,石墨电极为对电极,饱和甘汞电极(SCE)为参比电极,在室温离子液体中电化学还原2-硝基苯甲醚合成2-氨基苯甲醚。优化了电解实验条件,在最佳实验条件(E= -1.0 V, T=50 ℃, c=74.4 mmol·L-1, Q=6 F·mol-1, Y=10:1)下2-氨基苯甲醚的产率最高可达51.3%。在离子液体中电化学合成2-氨基苯甲醚,反应条件温和,避免了有毒易挥发的溶剂、催化剂及其他支持电解质等的使用;并实现了离子液体的重复利用,为2-氨基苯甲醚提供了一条新的绿色化合成路线。     

A tricarbonyl rhenium(I) complex with a pendant pyrrolidinium moiety as a robust and recyclable catalyst for chemical fixation of carbon dioxide in ionic liquid

A novel Re(I) complex covalently anchored with a pyrrolidinium moiety was successfully synthesized and used as an efficient and recyclable catalyst in the cycloaddition of CO2 with epoxides under mild reaction conditions to give excellent isolated yield and selectivity of cyclic carbonates in pyrrolidinium ionic liquid.     

Ionic liquid as an efficient promoting medium for fixation of CO2: clean synthesis of alpha-methylene cyclic carbonates from CO2 and propargyl alcohols catalyzed by metal salts under mild conditions

Reactions of propargylic alcohols with CO(2) in a [BMIm][PhSO(3)]/CuCl catalytic system to produce the corresponding alpha-methylene cyclic carbonates were conducted with high yields. Mild reaction conditions, enhanced rates, improved yields, and recyclable ionic liquid catalyst systems are the remarkable features exhibited in this process. Furthermore, the use of large amounts of tertiary amines as well as nitrogen-containing organic solvent as employed in previously studies was avoided.     

Polyaddition of bifunctional cyclic carbonate with diamine in ionic liquids: In situ ion composite formation and simple separation of ionic liquid

Polyaddition of bifunctional cyclic carbonates and diamines in ionic liquids proceeded smoothly to afford polyurethanes having hydroxyl groups in the side chain (i.e., poly(hydroxyurethane)). The reaction mixtures separated into ionic liquids and ionic composites consisting of poly(hydroxyurethane) and ionic liquids. The ionic composites originated from the interactions between hydroxyl groups in the side chains and the ionic liquids, confirmed by IR spectroscopic analysis. When the polyaddition was conducted in the mixed solvent consists of water and N‐n‐butylimidazolium hexafluorophosphate. After the reaction, the polymer and the ionic liquid could be separated easily. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4629–4635, 2009     

Efficient and Reusable Iron Catalyst to Convert CO2 into Valuable Cyclic Carbonates

The production of cyclic carbonates from CO₂ cycloaddition to epoxides, using the C-scorpionate iron(II) complex [FeCl₂{κ³-HC(pz)₃}] (pz = 1H-pyrazol-1-yl) as a catalyst, is achieved in excellent yields (up to 98%) in a tailor-made ionic liquid (IL) medium under mild conditions (80 °C; 1–8 bar). A favorable synergistic catalytic effect was found in the [FeCl₂{κ³-HC(pz)₃}]/IL system. Notably, in addition to exhibiting remarkable activity, the catalyst is stable during ten consecutive cycles, the first decrease (11%) on the cyclic carbonate yield being observed during the 11th cycle. The use of C-scorpionate complexes in ionic liquids to afford cyclic carbonates is presented herein for the first time.     

Synthesis of Cyclic Carbonate Catalyzed by DBU Derived Basic Ionic Liquids

In this work, 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU), 1,5‐diazabicyclo[4.3.0]‐5‐nonene (DBN), and imidazole (MIM)‐derived bromide ionic liquids (ILs) were synthesized and used to catalyze the cycloaddition reactions of carbon dioxide (CO₂) with several kinds of epoxides to form cyclic carbonates. The DBU derived bromide ionic liquid system was found to have the best catalytic activity among all the tested ILs. The influences of reaction conditions (including temperature, pressure and reaction time) on the reaction of CO₂ to propylene oxide (PO) were studied to show the best conditions of 120 °C, 1 MPa, 2.5 h catalyzed by 2 mol% DBU‐derived bromide ionic liquid, with the conversion of PO and the selectivity of propylene carbonate (PC) reaching 99% and 99%, respectively. Under the optimum reaction conditions, the ionic liquid system could be reused at least five times without decrease in selectivity and conversion. NMR spectroscopy and DFT calculations were used to reveal the hydrogen‐bond interaction between ionic liquids and reagent, based on which the reaction mechanism was proposed.     

Task-specific ionic liquid and CO2-cocatalysed efficient hydration of propargylic alcohols to α-hydroxy ketones

The hydration of propargylic alcohols is a green route to synthesize α-hydroxy ketones. Herein a CO₂-reactive ionic liquid (IL), [Bu₄P][Im], was found to display high performance for catalyzing the hydration of propargylic alcohols in the presence of atmospheric CO₂, and a series of propargylic alcohols could be converted into the corresponding α-hydroxy ketones in good to excellent yields. In the IL/CO₂ reaction system, CO₂ served as a cocatalyst by forming α-alkylidene cyclic carbonates with propargylic alcohols, and was released via the rapid hydrolysis of the carbonates catalysed by the IL. This is the first example of the efficient hydration of propargylic alcohols under metal-free conditions.     

The synthesis of quaternary ammonium salts from ammonium salts and dialkyl carbonate

Quaternary ammonium salts were synthesized from ammonium salts and dialkyl carbonates over an ionic liquid catalyst 1-ethyl-3-methylimidazolium bromide.     

新型Br?nsted酸性离子液体催化二氧化碳与环氧化合物偶联反应

设计合成了一系列由碳链长度可调节的Br?nsted酸中心阳离子及Lewis碱中心阴离子构成的酸性离子液体,,并应用于二氧化碳与环氧化合物的偶联反应合成环碳酸酯。考察了离子液体结构以及温度、压力和催化剂用量等参数的影响。结果表明,具有长碳链的离子液体表现出高催化活性及可重复使用性能。离子液体的酸性影响催化活性。     

Efficient catalytic synthesis of optically active cyclic carbonates via coupling reaction of epoxides and carbon dioxide

Chiral Co(salen) complexes bearing the Lewis acid of group 13 can efficiently catalyze the reactions of carbon dioxide with epoxides in the presence of catalytic amounts of alkali metal salts, quaternary ammonium halide or ionic liquids. They exhibited excellent activity for producing enantiomerically enriched cyclic carbonates.     

Heterogeneous electron transfer kinetics at the ionic liquid/metal interface studied using cyclic voltammetry and scanning electrochemical microscopy

The electrochemical behavior of a redox-active, ferrocene-modified ionic liquid (1-ferrocenylmethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) in acetonitrile and in an ionic liquid electrolyte (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) is reported. Reversible electrochemical behavior was observed in each electrolyte with responses typical of those for unmodified ferrocene observed in each medium. In the ionic liquid electrolyte, the diffusion coefficient of the redox-active ionic liquid increased by a factor of 5 upon increasing the temperature from 27 to 90 degrees C. The kinetics of electron transfer across the ionic liquid/electrode interface were studied using cyclic voltammetry, and the standard heterogeneous electron transfer rate constant, k (0) was determined to be 4.25 x 10 (-3) cm s (-1). Scanning electrochemical microscopy was then also used to probe the heterogeneous kinetics at the interface between the ionic liquid and the solid electrode and conventional kinetic SECM theory was used to determine k (0). The k (0) value obtained using SECM was higher than that determined using cyclic voltammetry. These results indicate that SECM is a very useful technique for studying electron transfer dynamics in ionic liquids.