1-十二烷基-3-甲基咪唑芳磺酸盐的微波辅助合成及表征

本文采用微波辅助合成技术,以N-甲基咪唑、溴代十二烷、苯(萘)磺酸钠为原料,经季铵化和阴离子交换两步反应,合成了1-十二烷基-3-甲基咪唑苯磺酸盐[C12mim][BS]和1-十二烷基-3-甲基咪唑萘磺酸盐[C12mim][NS],通过红外光谱和核磁共振氢谱对中间体和产物进行了结构表征,并对产物的表/界面活性进行了评价,探索了上述离子液体型磺酸盐表面活性剂在三次采油领域的潜在应用价值。     

离子液体-水界面可控合成银薄膜及其SERS研究

在互不相溶的离子液体-水(ILs-H2O)界面合成了由Ag颗粒组成的薄膜。采用不同的ILs,在1-癸基-3-甲基咪唑六氟磷酸盐-水([C10mim][PF6]-H2O)、1-癸基-3-甲基咪唑双三氟磺酰亚胺盐-水([C10mim][Tf2N]-H2O)和1-癸基-3-甲基咪唑四氟硼酸盐-水([C10mim][BF4]-H2O)界面分别合成了由Ag纳米片、纳米带和立方颗粒所组成的薄膜。所制备的Ag薄膜能够直接用作表面拉曼增强(SERS)研究的活性底物。而且,由纳米片以及纳米带组成的Ag薄膜显示出较强的SERS效应。     

一个物理化学设计实验的探讨与改进——离子液体溶液平均活度系数的测定

文章制备了溴化1-十二烷基-3-甲基咪唑[C12mim]Br和1-十二烷基-3-甲基咪唑四氟硼酸盐[C12mim][BF4]两种离子液体。在不同温度下,测定了两种离子液体水溶液的电导率,根据电导率-浓度曲线转折点求出了两种离子液体水溶液的临界胶束浓度。由Debye-Hücker和Osager-Falk-enhangen公式计算出离子液体的平均活度系数。结果表明：[C12mim]Br和[C12mim][BF4]的水溶液临界胶束分别为5.75×10-3 mol·L-1和6.00×10？3 mol·L-1。25℃下,平均活度系数随浓度的增大而降低。     

含离子液体的四氢呋喃-乙醇等压气液相平衡

选取了离子液体(IL)1-己基-2,3-二甲基咪唑醋酸盐([HMMIM][OAc])为四氢呋喃(THF)-乙醇共沸体系的萃取剂,测量了3种[HMMIM][OAc]摩尔分数下(x₃=0.005,0.008,0.010) THF-乙醇-[HMMIM][OAc]三元体系等压气液相平衡(VLE)数据。从VLE数据可知随着[HMMIM][OAc]含量的增加,THF相对乙醇的挥发度增大。当[HMMIM][OAc]加入量足够大时,THF与乙醇的共沸能够被打破,但[HMMIM][OAc]的加入会使平衡温度会升高。使用NRTL模型对VLE数据进行了拟合,得到了THF-乙醇-[HMMIM][OAc]三元体系的二元交互作用参数,并以此为基础计算出打破THF-乙醇体系共沸所需要的最小[HMMIM][OAc]摩尔分数为0.005 3,这一结果优于文献中报道的其他离子液体。     

离子液体催化氯乙酸甲酯合成氯乙酸-2-庚酯的研究

探索了离子液体催化氯乙酸甲酯和2-庚醇的酯交换反应,制备了1-甲基-3-（丙基-3-磺酸基）咪唑对甲苯磺酸盐[MIM-PS][PTSA]、1-甲基-3-（丙基-3-磺酸基）咪唑硫酸氢盐[MIM-PS][HSO₄]、1-丁基-3-甲基咪唑硫酸氢盐[BMIM]HSO₄、N-甲基咪唑磷酸盐[HMIM]H₂PO₄四种离子液体催化剂并用于酯交换反应,通过考察产品氯乙酸-2-庚酯收率,筛选出最佳催化剂[MIM-PS][PTSA]。并用[MIM-PS][PTSA]考察了反应温度、反应时间、催化剂添加量、催化剂循环使用对合成产品收率的影响。结果表明：将氯乙酸甲酯和2-庚醇在100 ℃下,添加5% [MIM-PS][PTSA]催化剂,反应6 h,合成氯乙酸-2-庚酯,收率可达76.3%,离子液体重复使用3次,氯乙酸-2-庚酯收率仍大于初次收率的95%。本实验用离子液体做溶剂或催化剂,反应条件稳定,可循环利用、对环境友好,且产品收率高,为工艺放大提供实验条件参考。     

咪唑类离子液体混合物用于二氧化硫高效吸收

开发易制备、价格便宜、面向SO₂气体高效分离的离子液体（ILs）,是当前ILs从实验探索迈向工业应用的难点与重大挑战。合成了不同摩尔比（3∶1、2∶1、1∶1、1∶2和1∶3）的1-乙基-3-甲基咪唑氯盐（[Emim][Cl]）和1-乙基-3-甲基咪唑乙酸盐（[Emim][OAc]）的离子液体混合物[Emim][Cl]_x[OAc]_1-x, 在测定其密度、黏度、热稳定性等基本物性数据的基础上,研究了[Emim][Cl]_x[OAc]_1-x混合物在不同温度和SO₂分压下的SO₂吸收能力。结果表明,[Emim][Cl]_x[OAc]_1-x能够有效地捕获SO₂。[Emim][Cl]与[Emim][OAc]之间存在协同促进作用,有利于实现SO₂高效吸收。[Emim][Cl]_0.33[OAc]_0.66混合液在1.0和0.2 atm（1 atm=101325 Pa）下捕获SO₂量分别为（1.34±0.08）和（0.74±0.05） g/g,与现有结果相比,混合物在SO₂捕获方面有明显优势。此外,这些离子液体混合物对二氧化硫的吸收和解吸具有良好的可逆性。     

咪唑盐离子液体的微波合成、表征及性质研究

通过微波辐射,在无溶剂的状态下以N-甲基咪唑为原料合成了4种氯化1-烷基-3-甲基咪唑盐([Bmim]Cl、[Omim]Cl、[C_12mim]Cl、[C_16mim]Cl)离子液体,并测定了离子液体的表面张力和吸水性能.     

氢氧化1-十二烷基-3-甲基咪唑的合成及其胶束催化糠醛制糠醇和糠酸

利用1-溴代十二烷和1-甲基咪唑为原料合成了碱性离子液体氢氧化1-十二烷基-3-甲基咪唑([C12mim]OH),采用IR和1HNMR对产物的结构进行了表征,并在20℃条件下测定了产物水溶液的表面张力(γ)。以[C12mim]OH作为胶束催化的表面活性剂,进行糠醛Cannizzaro反应制糠醇和糠酸;并在相同条件下与Triton X-100,Tween 80和十二烷基硫酸钠的催化效果进行了比较。结果表明,产物水溶液的临界胶束浓度(cmc)为0.001 mol·L-1,γcmc为29.2 mN·m-1;胶束催化是实现糠醛Cannizzaro反应,提高目标化合物选择性的有效方法,不同类型的表面活性剂催化效果为[C12mim]OH>Triton X-100>Tween 80>十二烷基硫酸钠。     

磁性离子液体1-甲基-3-烷基咪唑四卤化铁盐的合成及其物性表征

合成了4种1-甲基-3-烷基咪唑四氯化铁盐[Cnmim]FeCl4(n=2, 4, 6, 8)及3种1-甲基-3-丁基咪唑四卤化铁([C4mim]FeX4, X=Cl, Br)磁性离子液体,光谱结果表明,[Cnmim]FeCl4及[C4mim]FeBr4中阴离子单一,而[C4mim]FeClBr3及[C4mim]FeCl3Br中的阴离子为FeBr4-, FeBr3Cl-, FeCl2Br2-, FeCl3Br-, FeCl4-的混合物. 测定了其密度、粘度、电导率,磁性离子液体密度较大,25℃时为1.25~1.94 g/cm3;粘度较小,25℃时为21~65 mPa×s;电导率较大,30℃时为0.23~1.37 S/m. 并研究了其物性随温度及结构的变化规律.     

生物素中间体:四氢-7-乙氧羰基-3,3-五亚甲基-5-硫代-1-戊基-3H,5H-咪唑并[1,5c]噻唑的合成

以正庚醛为起始原料 ,α 溴化后与环己酮、氨、硫氢化钠反应合成 2 ,2 五亚甲基 5 戊基 3 噻唑啉 ,再用三氟化硼催化后 ,与异硫氰基乙酸乙酯的锂衍生物反应合成生物素中间体四氢 7 乙氧羰基 3 ,3 五亚甲基 5 硫代 1 戊基 3H ,5H 咪唑并 [1,5c]噻唑 ,收率达 17 1% ,通过 3步反应建立了生物素的立体化学骨架     

Investigation of enzymatic biodiesel production using ionic liquid as a co‐solvent

In this study, the lipase catalysed esterification reaction for biodiesel production was investigated in the presence of the ionic liquid [BMIM][PF₆]. Unlike regular organic solvents, many ionic liquids have no vapour pressure, and are therefore considered non‐volatile. When used in systems with enzyme catalysts, ionic liquids may enhance their activity, selectivity, and stability. The use of an enzyme (lipase) as a catalyst, and the ionic liquid as a solvent/immobilization agent also represents an environmentally friendly, “green” technology. Methyl acetate was used as the acyl acceptor as opposed to the more commonly used methanol due to the negative effects methanol and the glycerol by‐product has on lipase enzyme activity. The results of this research indicate that methyl oleate (i.e., biodiesel) was successfully produced, with an 80% overall biodiesel yield in the presence of ionic liquid, at a 1:1 ratio (v/v) to the amount of oil. This verified that the presence of an ionic liquid, at a specified amount, improved the activity of the lipase and the overall biodiesel yield. Results also indicate the addition of ionic liquid facilitated the separation of the methyl esters from the triacetylglycerol by‐product. The best conditions investigated was found to be: 14:1 molar ratio between oil and acyl acceptor; 20% (w immobilised lipase/w of oil; and a temperature in the range of 48–55°C. However, additional purification is required in order for the produced biodiesel to meet ASTM standards.     

酸性离子液体催化合成N,N’-亚甲基双丙烯酰胺

以N-甲基咪唑、2-氯乙基苯、硫酸氢钾合成1-甲基-3-[α-甲基-(4-磺酸苄基)]咪唑硫酸氢盐酸性离子液体,考察了酸性离子液体在甲醛和丙烯腈反应合成N,N’-亚甲基双丙烯酰胺(MBA)中的催化性能。结果表明,合成MBA的最佳反应条件为∶n(甲醛)∶n(丙烯腈)=1.2∶1.0,酸性离子液体用量为丙烯腈质量的8.0%,反应温度70℃,反应时间2 h。在该条件下MBA的收率>92%,纯度为98%以上,且反应结束后,产物易于分离,酸性离子液体可循环使用5次以上。     

In situ solvent formation microextraction based on a new ionic liquid for green preconcentration of trace amount of Cu (II) ions in water samples

A simple, fast, and effective analytical technique known as in situ solvent formation microextraction was used to preconcentrate/separate trace amounts of Cu(II) ions in water samples prior to determination by flame atomic absorption spectroscopy. In the present method, 6,6′-(1Z,1′Z)(butane-1,4-diylbis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)bis-3-bromophenol (Schiff base ligand) as the complexing agent and 1-methyl-3-pentylimidazolium bromide (ionic liquid) as an extracting agent were successfully synthesized and characterized by FTIR, C-NMR, and H-NMR spectroscopies. The effects of several analytical parameters on the method were studied and optimized, and the merits of the method, such as LDR (0.2–1000 µg L^?1), LOD (0.12 µg L^?1), RSD (4.1%), and preconcentration factor (70) were evaluated.     

离子液体[Bmim]BF_4合成反应后的纯化工艺

考察了离子液体[Bmim]BF4(四氟硼酸1-丁基-3-甲基咪唑)合成反应后纯化步骤中CH2Cl2用量、H2O用量及不同萃取水洗方式等因素对[Bmim]BF4得率的影响,得到了纯化时合理的CH2Cl2用量及H2O用量,质量比为:CH2Cl2:H2O:[Bmim]BF4粗品=7:3:10,其中H2O采用多次加入方式进行萃取水洗效果较好、离子液体的得率较高,纯化后[Bmim]BF4得率约为93.15%。     

Purification of undiluted ionic liquids from trace-colored impurities for spectroscopy by octadecylsilyl solid-phase extraction

Ionic liquids are often contaminated by trace-colored impurities. In this paper, a solid-phase extraction (SPE) method for purification of undiluted imidazolium ionic liquids was described. A SPE apparatus with octadecylsilyl (ODS) solid phase was proposed to separate these impurities from ionic liquids via hydrophobic interaction. Solid-phase extraction with ODS can improve the spectroscopic quality obviously for the tested ionic liquids. Without introducing any solvent to ionic liquid, the purified ionic liquid can be used directly in spectroscopic measurements. It was found that short alkyl chain ionic liquids were purified more efficiently than the long alkyl chain ones. This method can be used to purify the hydrogen-bonding anion containing ionic liquids, which cannot be decolorized efficiently by conventional active charcoal method. In comparison with other existing purification methods, ODS is advantageous to solve the purification problem of ionic liquids.     

离子液体中超低浓度混合酸催化纤维素制5-羟甲基糠醛

以绿色溶剂离子液体1-甲基-3-甲基咪唑磷酸二甲基盐(1-methyl-3-methyl-imidazole dimethyl phosphate,[DMIM][DMP])作为反应介质,研究超低浓度的混合酸--马来酸与盐酸(0.1%,质量分数)催化纤维素转化制备5-HMF。微波功率720W,反应时间9min,温度240℃,酸浓度0.1%,固液比1:50(质量比)为最佳反应条件,此条件下5-羟甲基糠醛的产率最高可达29.13%,转化效率为6.48mg/min。     

对苯二酚生产中副产品硫酸锰的分离纯化

采用重结晶、沉淀法和直接加热法对某化工厂对苯二酚生产过程中得到的硫酸锰副产品进行了分离纯化的实验室研究.以分离后产品中的二价锰含量评价纯化效果,沉淀法和直接加热两种方法能达到分离纯化目的,而重结晶法不能达到预期的分离效果.结果说明,直接加热法既能达到分离目的又能充分利用原料,且分离后得到硫酸锰和硫酸铵两种产品,是一种更简单可行的分离方法.     

氯铝酸盐离子液体催化转移烷基化反应研究

制备了阳离子分别为盐酸三乙胺、1-甲基-3-丁基咪唑和N-丁基吡啶的三种氯铝酸盐离子液体,并通过27AlNMR和吡啶及乙腈吸附的红外光谱等手段对其结构和酸性进行了表征,比较了上述三种离子液体催化2-甲基萘与1,2,4,5-四甲苯转移烷基化的反应性能。结果表明,阳离子结构不同的三种离子液体具有不同的催化性能,Et3NHCl-2AlCl3离子液体具有最高的催化反应活性和较高的2,6-二甲基萘选择性,在20℃下反应8h,2-甲基萘的转化率和2,6-二甲基萘选择性分别为36.8%和62.3%。     

Imidazolium salts as liquid coupling agents for the preparation of polypropylene‐silica composites

This article describes the application of ionic liquid 1‐decyl‐3‐methylimidazolium tetrafluoroborate in the preparation of polypropylene‐silica composites. The sol‐gel technology was used to prepare xerogel silica‐ionic liquid hybrid S1 , which was obtained as a free flowing powder of aggregated spherical particles. Ionic liquid free silica S2 was obtained by extraction and calcination of S1 . Melt blending of isotactic polypropylene with S1 and S2 afforded the composites C1 (with ionic liquid) and C2 (without ionic liquid), respectively. The presence of ionic liquid on the S1 silica surface promoted significantly improved silica dispersion in the polymer matrix and prevented compression of the silica particles. Furthermore, the crystallization temperature of composite C1 was significantly higher, which indicated that silica‐ionic liquid filler S1 acted as nucleating agent. The resistance to thermal decomposition of both composites was increased, but this was higher in the presence of ionic liquid. These results show that liquid salts can function as coupling agents and compatibalizers for the preparation of polymeric composites with differentiated properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Brnsted酸离子液体催化合成2-芳基-2,3-二氢-4(1H)-喹啉酮

制备了3种Brnsted酸离子液体:1-甲基-3-(3-磺丙基)咪唑硫酸氢盐([SO3H-pmim]HSO4)、1-(3-磺丙基)吡啶硫酸氢盐([SO3H-ppy]HSO4)、N-(3-磺丙基)三乙基铵硫酸氢盐([SO3H-ptea]HSO4),用于催化邻氨基苯乙酮和芳香醛的反应一锅法合成2-芳基-2,3-二氢-4(1H)-喹啉酮,考察了它们的催化活性和重复使用性能。结果表明,3种离子液体对邻氨基苯乙酮和芳香醛的反应均具有较高的催化活性,以[SO3H-ptea]HSO4催化性能更好。在60℃和无溶剂条件下,[SO3H-ptea]HSO4可以有效催化邻氨基苯乙酮和不同芳香醛反应,以68.3%～95.1%的收率得到目标化合物。离子液体经真空干燥重复使用5次,催化活性无明显下降。