羟基聚醚官能化杂多酸聚离子液体催化的连续酯化氧化合成环氧油酸甲酯

以乙二醇、环氧氯丙烷、三甲胺、三乙胺、三乙醇胺、H₄SiW₁₂O₄₀、H₃PW₁₂O₄₀为起始原料,经开环聚合、季铵化、分子自组装,构建了系列羟基官能化聚醚杂多酸聚离子液体HPIL-1～HPIL-6。聚离子液体兼具两亲活性、酸催化活性和氧化催化活性,以其为非均相催化剂,实现了油酸连续酯化、环氧化合成环氧油酸甲酯。当原料比n(甲醇)∶n(H₂O₂)∶n(油酸)∶n(聚离子液体)=500∶120∶40∶1,室温下酯化反应2.5h, 65℃下环氧化反应4h,环氧油酸甲酯产率92%。聚离子液体经离心分离、溶剂洗涤、真空干燥即可再生循环使用,循环使用5次,催化活性基本保持不变。     

新型N-甲基-N-烯丙基吗啡啉季铵盐类离子液体的合成

离子液体对某些无机和有机物溶解性能好、液态温度和电化学窗口范围宽、热稳定性高、易制备,因而近年来成为国内外研究的热点,目前的离子液体大多由烷基吡啶或双烷基咪唑季铵盐阳离子与氯铝酸根、氟硼酸根、六氟磷酸根以及其它大的阴离子构成,在季铵盐类离子液体中,     

吗啡啉功能化酸性离子液体的合成、表征及其催化酯化性能

制备和表征了三种新型质子酸离子液体: 吗啡啉硫酸氢盐([Hnhm]HSO4)、4-甲基吗啡啉硫酸氢盐 ([Hnmm]HSO4)和SO3H-功能化的4-(3-磺丙基)吗啡啉硫酸氢盐([C3SO3Hnhm]HSO4). 以氯乙酸(CAA)和乙醇合成氯乙酸乙酯的酯化反应考察了它们的酸性和催化活性, 并与1-(3-磺酸基)丙基-3-甲基咪唑硫酸氢盐、1-(3-磺丙基)吡啶硫酸氢盐、1-(3-磺丙基)-2-吡咯烷酮硫酸氢盐等三种具有不同氮杂环的SO3H-功能化酸性离子液体以及浓硫酸相对照. 结果表明, 上述SO3H-功能化离子液体对酯化反应的催化性能比非SO3H-功能化的[Hnhm]HSO4和[Hnmm]HSO4都高, 等同甚至优于浓硫酸. 当反应条件为: n(EtOH)∶n(CAA)∶n([C3SO3Hnhm]HSO4)＝1.3∶1∶0.2, 反应温度80 ℃, 反应时间3 h, 酯收率可达93.4%. 而且离子液体经真空干燥重复使用9次, 催化活性仍无明显下降. 以[C3SO3Hnhm]HSO4催化乙酸和不同醇的酯化反应获得较高的酯收率和选择性, 离子液体跟酯产物均能自动分相. 还考察了SO3H-功能化酸性离子液体对奥氏体316不锈钢的腐蚀性. 尽管SO3H-功能化离子液体与硫酸的酸性相近, 但对钢试样的腐蚀率不到硫酸的1/3.     

碱性离子液体催化合成碳酸甲乙酯

以碱性离子液体为催化剂,对碳酸二甲酯(DMC)和碳酸二乙酯(DEC)酯交换反应合成碳酸甲乙酯进行了研究.筛选出高催化活性的碱性离子液体1-丁基-3甲基咪唑丁酸盐([C4mim][CH3(CH2)2COO])为催化剂,详细考察了反应时间、温度、催化剂用量、原料配比等因素对酯交换反应的影响.实验结果表明,在反应温度为90℃,催化剂用量为6%(占反应物总质量百分数),n(DMC)∶n(DEC)=1.5∶1,反应时间为5h时,DEC的转化率高达48%.[C4mim][CH3(CH2)2COO]重复利用5次后仍保持较高的催化活性.     

碱性离子液体催化合成取代萘并吡喃衍生物

离子液体具有强极性、不挥发、化学稳定性好等特点,其极性和亲水/亲脂性可通过改变烷基碳链的长短和阴、阳离子的种类来进行调节,对其结构进行化学修饰,可以得到具有特定功能的离子液体[1-3],因此被誉为绿色溶剂和可设计的溶剂[2]。许多萘并吡喃衍生物都具有重要的生物活性和药     

碱性离子液体催化的Claisen-Schmidt缩合反应

合成了6种以N-甲基咪唑为基体的碱性离子液体, 以其作为催化剂, 在无溶剂条件下, 成功催化了Claisen-Schmidt缩合反应. 采用Hammett指示剂法对碱性离子液体的碱性强度和碱量进行表征. 实验结果表明, 此系列碱性离子液体对Claisen-Schmidt缩合反应具有较高的催化活性, 反应条件温和, 产物产率较高, 离子液体经简单处理后可多次循环使用, 催化活性未见明显降低.     

微波促进碱性离子液体催化合成查尔酮

以4-氯-1-丁醇,N-甲基咪唑和苯甲酸钠为原料,用微波法制得碱性离子液体{[OHBMIM]Ph COO(AIL)},其结构经FT-IR表征;以苯甲醛和苯乙酮为原料,AIL为催化剂,经微波促进的缩合反应合成了查尔酮(1),其结构经1H NMR和FT-IR确证。考察了AIL用量、微波功率、物料比和反应时间对1产率的影响。合成1的最佳反应条件为:AIL 1 mmol,苯甲醛5 mmol,n(苯甲醛)∶n(苯乙酮)=1.1,于微波功率140 W反应5 min,产率95.8%。AIL具有较好的循环使用性,循环使用6次,1产率没有明显降低。     

碱性离子液体催化合成三羟甲基丙烷

以碱性离子液体为催化剂, 构建了一种新型、高效的合成三羟甲基丙烷(TMP)的方法. 系统考察了催化剂类型、催化剂用量、反应温度、反应时间、甲醛与正丁醛用量比等因素对三羟甲基丙烷分离收率的影响. 研究结果表明: 碱性离子液体的催化性能与其碱强度息息相关, 碱性越强、催化活性越高. 最优条件下, 经离子液体[bmim]OH催化后, 可得到84%的TMP分离收率, 这一结果优于传统的有机无机碱催化体系且成功规避了传统碱催化合成TMP过程中繁琐的除盐过程、降低了过程能耗. 此外, 离子液体催化剂和未反应的丁醛均表现了良好的重复使用性能.     

酸性离子液体催化脂肪酸甲酯聚合制备二聚酸甲酯

 以 Brönsted-Lewis 酸性离子液体为催化剂, 用于催化生物柴油中不饱和脂肪酸甲酯聚合制备二聚酸甲酯反应, 考察了催化剂种类、催化剂用量、反应温度和时间等因素对聚合反应性能的影响, 得到较佳的反应条件. 结果表明, 当以 1-(3-磺酸)-丙基-3-甲基咪唑氯锌酸盐[HO3S-(CH2)3-mim]Cl-ZnCl2 (ZnCl2 摩尔分数为 0.67) 为催化剂, 生物柴油 15 g, m(生物柴油):m(离子液体) = 15:1, 于 240 oC 下反应 6 h 时, 二聚酸甲酯收率为 63.2%, 其中三聚体含量小于 5%. 另外, 该催化剂重复使用 5 次后, 二聚酸甲酯收率仍超过 63%, 表明其具有较好的重复使用性能. 离子液体的 Brönsted 和 Lewis 酸位的协同效应显著提高了其催化活性.     

咪唑阴离子型碱性离子液体的合成及其催化Knoevenagel缩合反应

设计合成了由1-丁基-3-甲基咪唑阳离子与咪唑阴离子搭配的[bmim]Im新型碱性离子液体并对其碱性进行研究.[bmim]Im离子液体的碱性与[bmim]OH的碱性接近且强于[bmim]OAc.在水溶液及室温条件下,2%的[bmim]Im离子液体对系列芳香醛与活泼的亚甲基化合物之间的Knoevenagel缩合反应具有较好的催化性能,目标产物的收率达到86%～95%,选择性为100%.同时,该催化剂体系具有良好的循环性能.     

Synthesis of methyl 12-benzoyldehydroabietate in ionic liquid

In the presence of the ionic liquid [bmim]Br/AlCl₃ as green reaction medium, methyl 12-benzoyldehydroabietate was synthesized through Friedel-Crafts acylation reactions on the aromatic ring of methyl dehydroabietate. The optimum synthetic conditions of the target product were found to be as follows: molar ratio of methyl dehydroabietate to [bmim]Br to AlCl₃ to benzoyl chloride 1:4:8:8, reaction temperature 40°C, reaction time 2 h. The target product was analyzed and characterized by means of IR, MS, NMR and elemental analysis. The results show that this novel method has the advantages of mild condition, short reaction time and environmental benignity. __________ Translated from Chemistry, 2008, 71(2): 138–143     

Poly(basic ionic liquid) coated magnetic nanoparticles: High-loaded supported basic ionic liquid catalyst

A novel poly(ionic liquid) (PIL) coated magnetic nanoparticle was synthesized by distillation-precipitation-polymerization of 1-vinyl-3- ethyl imidazolium in the presence of surface modified magnetic nanoparticles. The resulting catalyst was used as magnetic heterogeneous base catalyst for the synthesis of 4H-benzo[b]pyrans in water. The separation of the catalyst from the reaction mixture was readily achieved by simple magnetic decantation and the catalyst could be easily recycled without appreciable loss of catalytic activity. Because of polymer layers coated the surface of the magnetic nanoparticles, the catalyst has a high loading level of ionic liquid.     

Brønsted双核碱性离子液体的合成及其在制备生物柴油过程中的催化性能

以N-甲基吗啡啉和1,4-二溴丁烷为原料,通过两步法合成了新型Brønsted碱性双核离子液体.分别采用¹H-NMR、FT-IR和元素分析对合成的离子液体进行结构分析;采用TGA测试离子液体的热稳定性;同时测定了离子液体的溶解性和碱性.此外,考察了双核碱性离子液体在大豆油和甲醇酯交换反应中的催化活性.结果表明,当甲醇:大豆油=14:1(物质的量比)、离子液体用量为大豆油质量的5%、反应时间5 h、反应温度60 ℃时、生物柴油收率为 95.6%(质量分数),且离子液体经回收、真空干燥,重复使用6次后催化活性没有明显降低,仍能达到94%以上.     

Recent developments of task-specific ionic liquids in organic synthesis

Abstract

Task-specific ionic liquids (TSILs) have received increased attention over the past few years as it is possible to form any specific ionic liquid (IL) composition depending upon user's need of the desired physical, chemical, and biological properties. These fascinating materials have shown promising results in various areas such as organic synthesis, catalysis, and specially recent emerging trend of use as functionalized ILs for chiral and nanoparticle synthesis. Present review gives an update of recent developments in the field of TSILs with emphasis on their applications in organic synthesis.     

离子液体[bmim]PTSA的微波合成

近年来,随着绿色化学的兴起,离子液体作为一种新型的绿色溶剂已成为国内外科研工作者的研究热点之一.离子液体是由有机阳离子和无机阴离子组成的盐,可以根据需要控制阴阳离子的组成和结构,设计合成出不同特性的离子液体[1].     

Protic guanidinium ionic liquid as a green and highly efficient catalyst for the synthesis of functionalized spirochromenes under solvent-free conditions

A simple and efficient method for the synthesis of functionalized spirochromenes is explained using protic guanidinium ionic liquid as a catalyst under solvent-free conditions at room temperature. This procedure is simple, clean, and excellent yields are obtained in short reaction times.     

微波协同离子液体催化合成马来酸二丁酯

以马来酸酐和正丁醇为原料,用微波协同离子液体[HSO3-pmim]+[HSO4]-催化合成了马来酸二丁酯。通过单因素实验和正交试验考察催化剂种类、催化剂用量、马来酸酐与正丁醇物质的量比、微波功率、微波时间对马来酸二丁酯产率的影响。实验结果表明,马来酸二丁酯最佳合成条件为:马来酸酐与正丁醇物质的量比1∶4,以离子液体[HSO3-pmim]+[HSO4]-为催化剂,其用量为2.0g,微波功率为600W,微波时间为15min,马来酸二丁酯产率可达到99.36%。在微波辐射下,催化剂离子液体[HSO3-pmim]+[HSO4]-重复使用7次后活性没有明显降低,马来酸二丁酯产率仍高于96%,表明该催化剂具有较好的反应活性和稳定性。与常规加热方式相比,微波加热提高了反应效率,缩短了反应时间。     

Synthesis of methyl orange using ionic liquids

Two ionic liquids were synthesized, each system consisting of the 1-hexyl-3-methylimidazolium ion ([hmim]⁺) as the cation and either hexafluorophosphate ([PF₆]⁻), or perchlorate ([ClO₄]⁻) as the anions. This study involves the synthesis of methyl orange (4-[[(4-dimethylamino)phenyl]-azo] benzene sulfonic acid sodium salt) using the ionic liquids as replacement solvents for the reaction. The advantage of using ionic liquids as substitutes for organic solvents includes: recyclable/reclaimable solvents, stabilization of intermediates and higher product yields. The 1-hexyl-3-methylimidazolium derivatives can be used for syntheses conducted at low temperatures and are less toxic than typical organic solvents.     

Basic ionic liquid/FeCl3·6H2O as an efficient catalyst for AGET ATRP of methyl methacrylate

A basic ionic liquid, 1‐butyl‐3‐methyl imidazolium hydroxide ([Bmim]OH), was synthesized and used as the additives in an iron‐mediated atom transfer radical polymerization with activators generated by electron transfer (AGET ATRP) of methyl methacrylate in bulk and solution, using FeCl₃ · 6H₂O as the catalyst, ethyl 2‐bromoisobutyrate as the initiator, vitamin C (Vc) as the reducing agent, and tetrabutylammonium bromide or tetra‐n‐butylphosphonium bromide as the ligand. Catalytic amount of [Bmim]OH could enhance the polymerization rate and produce poly(methyl methacrylate) with controllable molecular weights and narrow molecular weight distributions (M_w/M_n = 1.3–1.4). The nature of controlled/“living” free radical polymerization in the presence of basic ionic liquid was further confirmed by chain‐extension experiments. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012