Synthesis of 2,4-diisopropyl-5,5-dimethyl-1,3-dioxane catalyzed by Br?nsted acidic ionic liquids

The acetalization reactions of isobutyraldehyde with 2,2,4-trimethyl-1,3-pentanediol （TMPD） for the synthesis of 2,4-diisopropyl-5,5-dimethyl-1,3-dioxsne were carried out under mild reaction conditions using four water-stable Brenstad-acidic task-specific ionic liquids （[HMIM]BF4, -SO3H funcUonalized acidic ionic liquid, -COOH functionalized acidic ionic liquid, [NMP][HSO4]） as environmentally benign catalysts for the first time. The process is highly effective and very selective. The -COOH functionalized Brensted acidic ionic liquid with the two acid sites （IL-3） exhibited the most excellent catalytic performance under mild reactlon conditions. The -COOH functionalized Brensted acidic ionic liquid could be conveniently separated from the product and easily recycled in subsequent runs.     

Ionic liquids containing the urea moiety for recognition of halides and complex anions

A series of novel imidazolium based ionic liquids containing the urea moiety were designed and synthesized for anion recognition. 1-Ethylurea-3-methylimidazolium acetate ([Eumim]OAc) was used as the receptor for the halides and complex anions (BF4-, PF6-, BPh4-). 1H NMR spectra showed that the urea protons and imidazolium C(2) proton of the receptor ([Eumim]OAc) moved upfield on addition of various anions. A Job plot showed that the [Eumim]OAc receptor formed a 1:1 complex with BPh4-. X-ray diffraction analysis and the molecular modeling study revealed that the conformations of [Eumim]OAc and [Eumim]BPh4 were different. The conformational change of the cation was caused by anion exchange, and may provide an alternative to current methods for recognition of anions.     

室温离子液体中金纳米粒子的电化学制备及其表征

室温离子液体1乙基3甲基咪唑四氟硼酸盐中,采用电化学牺牲阳极法直接从金属金制备了球形金纳米粒子,采用X射线衍射（XRD）、带有电子能谱仪（EDS）的扫描电子显微镜（SEM）对所制备样品的结构、组成以及形态进行了表征.结果表明,在本实验条件下制得的金纳米粒子为面心立方结构,纯度较高,基本呈球形,粒径平均尺寸为20nm.     

含磺酸离子的侧链液晶聚硅氧烷的合成与表征

液晶单体M1(4-烯丙氧基苯甲酰氧基-4′-甲氧基苯甲酰氧基联苯),M2(4-烯丙氧基苯甲酰氧基-4′-丁基苯甲酰氧基苯)和离子单体M3(4-烯丙氧基偶氮苯磺酸)与含氢聚硅氧烷进行共聚合反应,制备了含磺酸离子的侧链液晶聚硅氧烷·其结构和液晶性能通过红外光谱(IR),差示扫描量热法(DSC)、偏光显微分析法(POM)、热重分析法(TG)进行了表征·研究结果表明,离子基团的引入,降低了液晶性能,但是没有改变其液晶类型·     

双功能离子液催化的Knoevenagel反应

以L-脯氨酸和氢溴酸为原料,合成了L-脯氨酸离子液体,并将其固载于CuI之上,制成了双功能脯氨酸离子液,对Knoevenagel反应中催化剂的用量,反应时间,反应温度,反应溶剂等作了初步考察和优化,并得出比较适合的反应条件。这种双功能离子液具有可回收的优点,且催化剂比较稳定,可回收重复使用。     

Use of ionic liquid in leaching process of brass wastes for copper and zinc recovery

Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid (IL) 1-butyl-3-methyl-imidazolium hydrogen sulfate ([bmim]HSO₄) at ambient pressure in the presence of hydrogen peroxide (H₂O₂) and potassium peroxymonosulfate (oxone) as the oxidants. Parameters affecting leaching efficiency, such as dissolution time, IL concentration, and oxidizing agent addition, were investigated. The results show that [bmim]HSO₄ is an efficient IL for the brass ash leaching, providing the dissolution efficiencies of 99% for Zn and 24.82% for Cu at a concentration of 50vol% [bmim]HSO₄ in the aqueous solution without any oxidant. However, more than 99% of zinc and 82% of copper are leached by the addition of 50vol% H₂O₂ to the [bmim]HSO₄ solution. Nevertheless, the oxone does not show the promising oxidant behavior in leaching using [bmim]HSO₄.     

脂肪酶CCL催化醋酸乙烯酯与醇的转酯反应的实验探究

考察了在正己烷、AOT/异辛烷反胶束体系、[bmim][PF6]离子液体和[bmim][BF4]离子液体四种体系中脂肪酶CCL催化醋酸乙烯酯与异辛醇的转酯反应以及影响反应转化率的一些因素,确定了较为适宜的反应条件;进行了脂肪酶CCL催化醋酸乙烯酯与异辛醇的转酯反应酶的重复利用性实验;扩展了醇的种类,考察了直链醇（己醇）、不饱和醇（异戊烯醇）、2级醇（仲辛醇）在两种离子液体和正己烷中转化率。     

离子液体[Hnmp]HSO_4催化菜籽油制备生物柴油

制备了具有酸性功能的离子液体[Hnmp]HSO4,并用其催化菜籽油酯交换制备生物柴油.该离子液体表现出良好的催化活性及稳定性.在醇油比为8∶1、反应温度(100±2)℃、反应时间5h和[Hnmp]HSO4的用量为菜籽油质量的8%时,生物柴油收率可达85.4%.并且该离子液体有较好的稳定性,循环使用4次后仍有较高的催化性能.     

离子液体[BSMim]HSO4催化合成油酸甲酯的研究

制备了一种对水稳定的磺酸功能化咪唑离子液体1-甲基-3-丁磺酸基咪唑硫酸氢盐([BSMim]HSO4),并以其作为催化剂催化油酸酯化合成油酸甲酯。离子液体表现出良好的催化活性及稳定性。通过单因素实验确定最佳反应条件为:离子液体[BSMim]HSO4催化剂用量为油酸质量的20%,n(甲醇):n(油酸)=3∶1、反应温度75℃、反应时间4h,酯化率达85.3%以上,此外离子液体还具有稳定性好、可循环使用等特点。     

离子液体N-丙基-吡啶二氰胺盐[C3py][DCA]水溶液的体积和表面性质

在T=(288.15～318.15)K温度范围内,测定了不同质量摩尔浓度的离子液体N-丙基-吡啶二氰胺[C_3py][DCA]水溶液的密度和表面张力。根据密度值计算了不同浓度[C_3py][DCA]水溶液的平均摩尔体积和热膨胀系数,水溶液平均摩尔体积随着温度和质量浓度的升高而增大,热膨胀系数随着温度的升高而增大。并提出了一种估算水溶液表面张力的经验方程。预测值与实验值具有较好的一致性。     

Thermodynamic characterization of two novel spin-crossover complexes

Spin-crossover complexes are of great interest to the scientists because of their potential application in molecular-based electronic devices. Some octahedral metal compounds with 3dn (4 ≤ n ≤ 7) configuration can induce a spin state conversion through a fine tuning condition (temperature, pressure, light irradiation, etc.). If the conversion occurs reversibly with a hystersis loop and color change, it will make the system possessing memory effect. The memory effect can be magnified and the …     

室温离子液体[Emim]BF4及其水溶液体系的比热容测定

在温度为298.15～343.15K,质量分数为25%～100%的条件下,采用Calvet微量量热仪测 定了室温离子液体四氟硼酸1-乙基-3-甲基咪唑([Emim]BF₄)及其水溶液体系的比热容。建立了该体系的比热容与温度和浓度的经验关联式,并比较了该体系的差示扫描量热计(DSC)所测得的实验数据和现象。研究认为Calvet微量量热法更适于测量含挥发性溶剂的体系。     

Property variation of ionic liquid [Bmim][AuCl4] immobilized on carboxylated polystyrene submicrospheres with a small surface area

In order to understand the effect of surface chemical groups on the immobilized species, Au-containing imidazolium-based ionic liquid (IL) [Bmim][AuCl4] was intentionally immobilized on polystyrene (PS) submicrospheres (d～300 nm) with a very small surface area (4-10 m2/g), which possess carboxyl-moiety (COONa or COOH) on the surface. The behavior of immobilized [Bmim][AuCl4 ] on the two types of submicrospheres was investigated by transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and powder X-ray diffraction (XRD). It was revealed that the melting points (Tm) of [Bmim][AuCl4 ] that had been immobilized on PS-COONa and PS-COOH submicrospheres were decreased by 2.7 and 4.1℃, respectively. The interaction mechanism between the IL and submicrosphere surface moieties was further analyzed by X-ray absorption fine structure (XAFS) analysis. The data indicated that the coordination environment of Au species changed markedly when [Bmim] [AuCl4] was immobilized on the surfaces of PS-COONa and PS-COOH submicrospheres, as illustrated by the decrease in white line peak intensity. The effect of surface COOH groups on Tm depression and the white line peak intensity of the XANES spectrum is more pronounced than that of COONa groups, most likely due to the possible hydrogen bond formation between the COOH group and [Bmim]+.     

离子液体介质中Knoevenagel缩合反应研究

以亲水性离子液体1-丁基-3-甲基咪唑对甲基苯磺酸盐作反应介质,醋酸铵为催化剂,研究了不同的芳香醛和脂肪醛与活泼亚甲基类化合物氰乙酸乙酯进行Knoevenagel缩合反应.反应产物经熔点、核磁共振谱、GS-MS、气相色谱等表征.结果表明,该方法产率高,速度快,选择性好,所使用的离子液体能够重复使用.     

离子液体1-丁基-3-甲基咪唑磷酸二丁酯的制备与应用

以磷酸三丁酯和N-甲基咪唑为原料,一步合成出了1-丁基-3-甲基咪唑磷酸二丁酯盐。该产品为一种新型的水溶性离子液体,浅棕色,其在25℃下的黏度和密度分别为3.45×10^-3Pa·s和1.045kg/m³。经电喷雾质谱测定其阴阳离子分别为磷酸二丁酯[(BuO)₂P(O)O]^-和1-丁基-3-甲基咪唑。由于空间位阻的影响,无论磷酸三丁酯和N-甲基咪唑的摩尔比如何,其产物中只有磷酸二丁酯阴离子,因此产物纯度高,易分离。实验表明,该离子液体对汽油中的3-甲基噻吩和二苯并噻吩具有良好的萃取效果,可望用于汽柴油的脱硫过程。     

烷基咪唑氟硼酸盐离子液体的合成与溶剂性质研究

研究了反应温度、时间和溶剂等对烷基咪唑氟硼酸盐室温离子液体[R1R2Im]BF4产率的影响,考察了该离子液体溶剂的性质。结果表明,[R1R2Im]BF4与油品中的脂肪族烃类组分不能互溶,但对部分含硫含氮组分均有一定的溶解度,同时还能溶解具有Lewis酸性的AlCl3和杂多酸络合物以及具有加氢活性的无机盐,这为开发Lewis酸催化或加氢催化等离子液体油品液/液双相催化体系奠定了基础。运用量子化学计算方法,考察了[R1R2Im]BF4的电导率与离子液体的分子结构的内在联系。结果表明,当阴离子相同时,N 烷基咪唑阳离子的体积越大,对应的离子液体的电导率越小。     

离子液体中α,α′-双亚苄基环烷酮的绿色合成

报道了在[bmim]BF4离子液体介质中,以InCl3.4H2O为催化剂,经芳醛与环烷酮缩合制备α,α′-双亚苄基环烷酮的新方法.与文献方法相比,该方法具有反应条件温和,产率高,易分离,操作简便、安全,对环境友好等诸多优势.     

[bmim]BF4离子液体的制备及其催化酯化反应研究

本文采用一步环合法合成了N-甲基咪唑,再由N-甲基咪唑和溴代正丁烷合成了中间体溴化1-丁基-3-甲基咪唑,中间体再经过离子交换得到1-丁基-3-甲基咪唑四氟硼酸盐（[bmim]BF4）离子液体．在该离子液体介质中,氯苄和乙酸钠反应高效合成了乙酸苄酯．结果表明：以[bmim]BF4为溶剂和催化剂乙酸钠与苄氯的摩尔比为1．4：1,反应温度为60℃,反应时间为2．5h,氯苄转化率可达95％．而且产物易于分离,离子液体可重复使用．中间体和产物结构经Fr—IR表征．     

[bmim]PTSA催化合成乙酸正戊酯的研究

用微波方法制备了[bmim]PTSA离子液体,并应用于催化合成乙酸正戊酯反应中,研究了影响酯化反应的各种因素。结果表明：离子液体[bmim]PTSA是该酯化反应良好溶剂和催化剂,离子液体用量15mL,醇酸摩尔比1．2：1．0,反应时间1．5h,酯化率达96．7％。离子液体易分离回收,可重复使用。     

药物中间体乙酸苯酯的绿色合成研究

以离子液体1-丁基-3-甲基-咪唑四氟硼酸盐(BMIMBF4)为催化剂和反应媒介,苯酚和乙酸酐为原料合成乙酸苯酯,考察了离子液体用量、底物配比、反应温度和时间对合成乙酸苯酯反应性能的影响.结果表明,反应8 h乙酸苯酯的产率即可达86%.该方法反应条件温和,不使用任何有毒有害的催化剂和易挥发的有机溶剂,合成工艺简单,对设备要求低,产率高,离子液体可以循环使用,是一种绿色高效的合成乙酸苯酯的新方法.