Molecular iodine in [bmim][BF4]: a highly efficient green catalytic system for one-pot synthesis of 1,3-oxathiolan-5-one

Aldehydes and mercaptoacetic acid are coupled in the presence of a catalytic amount of economical and non-toxic molecular iodine in [bmim][BF₄] ionic liquid under mild conditions to afford the corresponding 1,3-oxathiolan-5-one in excellent yields. Molecular iodine acts faster in ionic liquids when compared to conventional solvents such as DMSO, DMF, ethyl acetate, and acetonitrile. The recovered ionic liquids can be recycled in subsequent reactions with consistent activity.     

Molecular Iodine in Ionic Liquid: A Green Catalytic System for Esterification and Transesterification

Esterification of carboxylic acids and transesterification of β-ketoesters with alcohols have been developed using a catalytic amount of iodine in polyethylene glycol (PEG) ionic liquid (IL 1000) to afford the corresponding esters in good yields. By simple separation of the ionic-liquid phase containing the iodine, the system of I₂/IL 1000 can be reused several times.     

Hypervalent Iodine(III) Reagent Mediated Synthesis of 2‐Methylbenzofuran Derivatives by Pummerer‐type Reaction in Ionic Liquid

An efficient route for the synthesis of 2‐methylbenzofuran derivatives utilizing hypervalent iodine(III) reagent and a‐(methylthio)acetone via Pummerer‐type reaction in ionic liquid is described.     

Electrical,optical and photoelectrochemical studies on a solid PEO-polymer electrolyte doped with low viscosity ionic liquid

Solid polymer electrolyte (PEO:KI:I₂) membranes doped with low viscosity (34 cP at 25 °C) ionic liquid EMImTFSI (1-ethyl 3-methylimidazolium bis(trifluoromethylsulfonyl)imide) showing plasticizing effect as well as improved dye sensitized solar cell efficiency have been reported first time. Apart from ionic conductivity enhancement due to large number of free charge carriers provided by ionic liquid (IL) it assist in reducing cystallinity of polymer electrolyte matrix which was confirmed by polarized optical microscopy (POM). Cyclic voltammetry was carried out to study the reactions of iodide, iodine and IL in polymer electrolyte matrix.     

Ionic liquid crystal as a hole transport layer of dye-sensitized solar cells

Use of a new ionic liquid crystal, 1-dodecyl-3-methylimidazolium iodide, and iodine as an electrolyte of dye-sensitized solar cells leads to a high short circuit photocurrent density and a high light-to-electricity conversion efficiency, due to a self-assembled structure of the imidazolium cations, resulting in high conductivity of the electrolyte.     

染料敏化太阳电池用聚合物电解质

综述了本研究小组近年来用于染料敏化太阳电池中聚合物电解质的研究概况.设计合成了几类性能优良的聚合物电解质,较好地改进了液体电解质染料敏化太阳电池(DSSC)的使用稳定性,研究结果具有实际应用的价值,并提出了此领域研究今后的发展方向.     

Hierarchically Porous Poly(ionic liquid) – Organic Cage Composite Membrane for Efficient Iodine Capture

The effective capture of iodine with high volatility and poisonousness is significant for reprocessing the spent nuclear fuel. In this article, we report a hierarchically porous poly(ionic liquid)-organic cage composite membrane (PIL@CC3) possessing a gradient content distribution of CC3 cage crystals throughout the membrane to capture iodine vapor. The introduction of microporous CC3 can significantly enhance the uptake capacity of iodine up to 980 mg g⁻¹, which is superior to that of a pristine PIL membrane carrying large meso- and macropores (99 mg g⁻¹), and CC3 crystalline powder (662 mg g⁻¹). Such enhanced performance benefits from the micro-meso-macroporous structure of the PIL@CC3 membrane in which the large meso- and macropores facilitate the mass transfer of iodine molecules from the external environment into the surface of the CC3 crystal, followed by diffusion of iodine molecules from the CC3 surface into the interior and exterior pores of the CC3 crystal. In addition, the asymmetric distribution of CC3 crystals across the PIL@CC3 membrane also displays its advantage in intercepting trace iodine, revealing its great potential for practical application. This study provides an idea for constructing hierarchically porous membrane composites for the removal of toxic vapors.     

Interaction of polyvinylpyrrolidone and iodine

A nonsolvent preparation of the polyvinylpyrrolidone (PVP) complex provides new insight into the nature of the polymer-iodine interaction. The preparation is obtained by simply mixing PVP with crystalline iodine and is of interest because it provides a system in which no interfering ions are present and only one type of iodine is initially present. The iodine is shown to undergo hydrolysis with moisture in the polymer to give iodide and hypoiodite. The ionic forms of iodine appear to associate with the molecular iodine, resulting in the final stable PVP-iodine complex.     

Synthesis of 2-Arylquinazolin-4(3H)-one Derivatives Catalyzed by Iodine in [bmim+][ ]

Controlling selectivity of the reactions of aromatic aldehydes and 2-aminobenzamide in ionic liquid catalyzed by iodine at either room temperature or at 80 °C under nitrogen resulted in the synthesis of (E)-Schiff bases, 2,3-dihydro-2-arylquinazolin-4(1H)-one and 2-arylquinazolin-4(3H)-one derivatives, in excellent yields.     

Tetrazole thiolate/disulfide organic redox couples carrying long alkyl groups in dye-sensitized solar cells with Pt-free electrodes

Colorless tetrazole thiolate/sulfide redox couples carrying long alkyl groups, such as n-butyl, n-hexyl, and n-octyl groups, were synthesized as electrolytes in iodine/iodide-free dye-sensitized solar cells (DSSCs). Among N719/TiO₂-based DSSCs employing these highly soluble redox couples for 3-methoxypropionitrile (3-MPN) and ionic liquid with PEDOT counter electrode, the DSSC with n-hexyl redox analogue gave an optimized η value of 4.32%. An observed respectable quantum efficiency for 400–500 nm light is in sharp contrast to the decreased performance for iodine/iodide systems that originates from the substantial light absorption of iodine. On the other hand, the redox possessing n-octyl group significantly lowered the cell performance, which could be a result of the much increased resistance of electrolyte diffusion in the DSSC.     

Interaction of anti-thyroid drugs with iodine: the isolation of two unusual ionic compounds derived from Se-methimazole

The inhibition of lactoperoxidase (LPO)-catalyzed iodination of l-tyrosine by the anti-thyroid drug methimazole (MMI) and its selenium analogue (MSeI) is described. MSeI inhibits LPO with an IC(50) value of 12.4 microM, and this inhibition could be completely reversed by increasing the peroxide concentration. In addition to the inhibition, MSeI reacts with molecular iodine to produce novel ionic diselenides, and the nature of the species formed in this reaction appear to be solvent-dependent. The formation of ionic species in the reaction is confirmed by single-crystal X-ray studies, FT-IR and FT-Raman spectroscopic investigations. This study provides the first experimental evidence that MSeI not only effectively inhibits the LPO-catalyzed iodination of tyrosine, but also reacts with I(2) to produce novel ionic diselenides. These results also suggest that MSeI reacts with iodine, even in its oxidized form, to form ionic diselenides containing iodide or polyiodide anions, which might be effective intermediates in the inhibition of thyroid hormones.     

A Green Synthesis of Pyrrolo[1,2‐a]quinazolin‐5(1H)‐one Derivatives in Ionic Liquids Catalyzed by Iodine

A series of 2,3,3a,4‐tetrahydro‐3a‐methylpyrrolo[1,2‐a]quinazolin‐5(1H)‐one derivatives were synthesized by a reaction of 2‐aminobenzamide and 5‐chloropentan‐2‐one at 80 °C catalyzed by iodine in ionic liquid of [BMIm]Br. Compared with the other methods, this novel method has the advantages of milder reaction conditions, high yields, environmental benignity, and metal‐free catalyst.     

Supported ionic liquid catalysis--a new concept for homogeneous hydroformylation catalysis

The new concept of supported ionic liquid catalysis involves the surface of a support material that is modified with a monolayer of covalently attached ionic liquid fragments. Treatment of this surface with additional ionic liquid results in the formation of a multiple layer of free ionic liquid on the support. These layers serve as the reaction phase in which a homogeneous hydroformylation catalyst was dissolved. Supported ionic liquid catalysis combines the advantages of ionic liquid media with solid support materials which enables the application of fixed-bed technology and the usage of significantly reduced amounts of the ionic liquid. The concept of supported ionic liquid catalysis has successfully been used for hydroformylation reactions and can be further expanded into other areas of catalysis.     

Self-assembly and enhanced photocatalytic properties of BiOI hollow microspheres via a reactable ionic liquid

BiOI uniform flowerlike hollow microspheres with a hole in its surface structures have been successfully synthesized through an EG-assisted solvothermal process in the presence of ionic liquid 1-butyl-3-methylimidazolium iodine ([Bmim]I). The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), nitrogen sorption, and diffuse reflectance spectroscopy (DRS). A possible formation mechanism for the growth of hollow microspheres was discussed. During the reactive process, ionic liquid not only acted as solvents and templates but also as an I source for the fabrication of BiOI hollow microspheres and was vital for the structure of hollow microspheres. Additionally, we evaluated the photocatalytic activities of BiOI on the degradation of methyl orange (MO) under visible light irradiation and found that as-prepared BiOI hollow microspheres exhibited higher photocatalytic activity than BiOI nanoplates and TiO(2) (Degussa, P25) did. On the basis of such analysis, it can be assumed that the enhanced photocatalytic activities of BiOI hollow microspheres could be ascribed to its energy band structure, high BET surface area, high surface-to-volume ratios, and light absorbance.     

1-甲基-3-己基咪唑碘的合成及在染料敏化太阳电池中的应用

利用高压釜使1-甲基咪唑和碘代正己烷直接反应生成离子液体1-甲基-3-己基咪唑碘, 并考察了温度对反应的影响. 结果表明, 升高反应温度, 可使1-甲基咪唑和碘代正己烷按化学计量比进行反应, 产率近100%, 该方法操作简单, 所得产品纯度高, 反应过程不需要使用有机溶剂, 且对环境友好. 同时还测量了I-3在1-甲基-3-己基咪唑碘和1-甲基咪唑混合液中的表观扩散系数及其所组成的染料敏化太阳电池的光伏性能.     

Influence of water on the surface of the water-miscible ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate: a sum frequency generation analysis

Sum frequency generation spectroscopy (SFG) was used to study the influence of water on the surface of the water-miscible ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate. The orientation of the cation at the gas-liquid interface was analyzed as a function of ionic liquid concentration in water for concentrations from 0 to 1 mole fraction of the ionic liquid. The cation was found to be oriented with the imidazolium ring nearly parallel to the surface plane with a tilt angle > or = 70 degrees when the ionic liquid was dry. Furthermore, no noticeable change in the orientation was observed when high concentrations of water were mixed with the ionic liquid. The cation butyl chain is projecting into the gas phase with a CH(3) tilt angle of 54 +/- 2 degrees when the ionic liquid is dry and 46 +/- 4 degrees when mixed with water. Water is oriented at the surface only for concentration < or = 0.02 mole fraction of the ionic liquid. At higher ionic liquid concentrations (mole fractions > or = 0.05) the gas-liquid interface resembles that of the pure ionic liquid.     

基于双醛基功能化离子液体构建电化学免疫传感器

合成了含双醛基的离子液体,此离子液体一端的醛基与修饰在电极表面的氨基发生共价键作用,将离子液体修饰在电极表面,另一端的醛基可用来固定抗体,构建电化学免疫传感器,实现对心肌肌钙蛋白I(cTnI)的检测。离子液体通过共价键作用固定在电极表面,不仅减少了从电极表面向检测溶液的渗透,提高传感器的稳定性,而且还可以直接固定抗体,不需要使用其他交联试剂;同时,离子液体可增强传感界面的导电性,提高传感器的灵敏度。在优化的实验条件下,传感器的线性范围为0.1~40 ng/mL,检出限为0.06 ng/mL。     

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。     

聚苯胺在离子液体/水体系中的微乳液法合成

通过乳化剂OP-10的乳化作用,将油相为溶有苯胺单体的1-丁基-3-甲基咪唑六氟磷酸盐([bmim]PF6)离子液体与水形成了水包油型微乳液.利用该微乳液制备了纳米粒径的导电聚苯胺颗粒.红外光谱和能量散射谱分析结果表明,离子液体负离子已掺杂进入聚苯胺分子链,所得聚苯胺颗粒热稳定性和电化学稳定性好,且具有良好的充放电性能.     

染料敏化纳米薄膜太阳电池中离子液体基电解质的研究进展

综述了离子液体基电解质在染料敏化纳米薄膜太阳电池中的研究及应用进展，详细论述了多种离子液体基电解质系统对染料敏化纳米薄膜太阳电池性能的影响，并比较了这些系统的优缺点. 根据胶凝剂的不同分别论述了离子液体基电解质的固化及其对电池性能的影响. 评述了离子液体基电解质在大面积电池中的应用，并对离子液体基电解质未来发展方向进行了展望.