[bmin]Cl/[FeCl3]离子液体催化的苯与1-十八烯烷基化反应

Abstract The study on the catalysis of ionic liquids for alkylation of benzene with 1-octadecene to synthesize LAB （linear alkylbenzenes） was performed. The results showed that the most important factor that governed the conversion of olefin and selectivity of LAB was reaction temperature. Moreover, the effects of different ionic liquids and molar ratio of benzene to 1-octadecene on the conversion and selectivity were obviously in different degrees. The reaction temperature, molar ratio of benzene to 1-octadecene and the amount of catalyst were lower, compared with the traditional reaction technologies. The experimental results demonstrated that the ionic liquid had higher activity at 30℃, with over 98% selectivity of monoalkylbenzene and 100% conversion of the olefin at the molar ratio 0.08 of FeCl3 in ionic liquid to 1-octadecene and 10 for benzene to 1-octadecene.     

Highly selective synthesis for 4,4′-bisphenol F from phenol and formaldehyde catalyzed with [C_4mim][HSO_4] ionic liquid

The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-bisphenol F were investigated. The hydrogen bonding between the hydroxyl of phenol and the C2-position hydrogen of imidazole moiety in hydrophilic imidazole-based ionic liquid has important influence on the selectivity for 4,4′-bisphenol F, and under the conditions of the molar ratio of phenol/[C4mim][HSO4] 1:1, reaction temperature65 °C and the theoretical molar ratio of phenol/formaldehyde 2:1, the selectivity for 4,4′-bisphenol F reached69.1%. Compared with the high phenol/formaldehyde ratio reported in literatures, the low molar ratio of phenol/formaldehyde and the low reaction temperature can greatly reduce energy consumption, and has important significance for industrial application.     

Ionic liquid catalyzed solvent-free synthesis of chalcone and its derivatives under mild conditions

An ionic liquid(IL) catalyzed solvent-free process was developed for the direct synthesis of chalcone and its derivatives by using substituted acetophenones and benzaldehydes via aldol reaction under mild conditions. A series of acidic and basic ILs were selected and screened. The influences of cations and reaction conditions on product yield and selectivity were systematically investigated. The [Bmim]OH was identified as the optimal IL, with the highest yield and selectivity reaching up to 96.7% and 100%, respectively. A reaction mechanism-based kinetic model was established and regressed with experimental data, revealing the b-Hydroxylketone dehydrolysis with activation barrier of 37.8 k J·mol~(-1) was observed as the ratecontrolling step.     

SO_3H-功能化离子液体催化4,4'-MDC合成反应

The synthesis of methylene diphenyl dimethylcarbamate (4,4′-MDC) from methyl N-phenyl carbonate (MPC) and formaldehyde (HCHO) was conducted in the presence of sulfonic acid-functionalized ionic liquids (ILs) as dual solvent-catalyst. The influences of the kind of anion in the ionic liquids, reaction conditions and the recycle of the ionic liquid on 4,4′-MDC synthesis reaction were investigated. In addition, the acid strength of ILs was determined by the Hammett method with UV-visible spectroscopy, and the acid strength-catalytic activity relationship was correlated. The activity estimation results showed that [HSO3-bmim]CF3SO3 was the optimal dual solvent-catalyst. Under the suitable reaction conditions of 70°C, 40 min, molar ratio of nMPC/nHCHO 10/1 and mass ratio of WILs/WMPC 4.5/1, the yield of 4,4′-MDC based on HCHO was 89.9 % and the selectivity of 4,4′-MDC with respect to MPC was 74.9%. Besides, [HSO3-bmim]CF3SO3 was reused four times after being purified and no significant loss in the catalytic activity was observed.     

Simultaneous Synthesis of Dimethyl Carbonate and Poly（ethylene terephthalate） Using Alkali Metals as Catalysts

Dimethyl carbonate （DMC） and poly（ethylene terephthalate） was simultaneously synthesized by the transesterification of ethylene carbonate （EC） with dimethyl terephthalate （DMT） in this paper. This reaction is an excellent green chemical process without poisonous substance. Various alkali metals were used as the catalysts. The results showed alkali metals had catalytic activity in a certain extent. The effect of reaction condition was also studied. When the reaction was carded out under the following conditions： the reaction temperature 250℃, molar ratio of EC to DMT 3 ： 1, reaction time 3h, and catalyst amount 0.004 （molar ratio to DMT）, the yield of DMC was 68.9%.     

[bmim]Cl／FeCl3离子液体催化苯与乙烯烷基化反应的新型机理

Up to now the mechanism of Friedel-Crafts reactions catalyzed by ionic liquid have not been fully understood, while carbocation mechanism was assumed. It was found that the source of H and the route of reaction initiated the alkylation of benzene with ethylene catalyzed by [bmim]Cl/FeCl3 ionic liquid. The fact that dewatered ionic liquids have catalytic activity for the alkylation of benzene with ethylene suggests that there exists a new catalytic route. The distinctly Bronsted acid properties of 2-H in [bmim]Cl were found through FT-IR and HNMR analysis of [bmim]Cl after titration with water free KOH in alcohol solution. In addition, the chemical shifts of proton on the [bmim]Cl ring, especially 2-H, are sensitive to the change of FeCl3 content and shifted downfield when FeCl3 was added into [bmim]Cl to form ionic liquid. Thus 2-H was easy to be disengaged from imidazolium ring with formation of H^ to initiate the reaction. The isotope-substituted method was employed to prove this mechanism, through the GC-MS analysis of alkylation products of deuterated benzene with ethylene. The route of alkylation catalyzed by FeC13 ionic liquid was found to follow the carbocation mechanism, the resource of H was presented and proved using HNMR analysis of ionic liquid to inspect the intensity change of 2-H. It was found that the intensity of 2-H reduced 23% after reaction showing that the H arising from alkylation reaction was supplied by 2-H on the imidazole ring.     

Kinetics study of the N-formylation of aniline with DMF catalyzed by temperature-controlled Brùnsted ionic liquids

A series of SO₃-functional Br?nsted acidic ionic liquids(SBAILs) were prepared to catalyze the Nformylation of aniline with DMF.The reaction conditions such as ionic liquid type,reaction temperature.catalyst loading and molar ratio of reactants were investigated.To the best of our knowledge,kinetic model for the N-formylation of aniline with DMF using SBAIL was firstly built and simulated.The studies on the reaction order of the reaction were evaluated by initial concentration method,...     

New Alkylation Route of Benzene with Ethylene Catalyzed by [bmim]Cl/FeCl_3 Ionic Liquid

Up to now the mechanism of Friedel-Crafts reactions catalyzed by ionic liquid have not been fully understood, while carbocation mechanism was assumed. It was found that the source of H and the route of reaction initiated the alkylation of benzene with ethylene catalyzed by [bmim]Cl/FeCl3 ionic liquid. The fact that dewatered ionic liquids have catalytic activity for the alkylation of benzene with ethylene suggests that there exists a new catalytic route. The distinctly Bronsted acid properties of 2-H in [bmim]Cl were found through FT-IR and HNMR     

Lipase-catalyzed Synthesis of Caffeic Acid Phenethyl Ester in Ionic Liquids： Effect of Specific Ions and Reaction Parameters

Caffeic acid phenethyl ester（CAPE） is a rare, naturally occurring phenolic food additive. This work systematically reported fundamental data on conversion of caffeic acid（CA）, yield of CAPE, and reactive selectivity during the lipase-catalyzed esterification process of CA and phenylethanol（PE） in ionic liquids（ILs）. Sixteen ILs were selected as the reaction media, and the relative lipase-catalyzed synthesis properties of CAPE were measured in an effort to enhance the yield of CAPE with high selectivity. The results indicated that ILs containing weakly coordinating anions and cations with adequate alkyl chain length improved the synthesis of CAPE. [Emim][Tf2 N] was selected as the optimal reaction media. The optimal parameters were as follows by response surface methodology（RSM）： reaction temperature, 84.0 °C; mass ratio of Novozym 435 to CA, 14︰1; and molar ratio of PE to CA, 16 ︰ 1. The highest reactive selectivity of CAPE catalyzed by Novozym 435 in [Emim][Tf2 N] reached 64.55%（CA conversion 98.76% and CAPE yield 63.75%, respectively）. Thus, lipase-catalyzed esterification in ILs is a promising method suitable for CAPE production.     

Stability of penicillin G in ionic liquid [Bmim]PF6

The extraction of penicillin G by ionic liquid[Bmim]PF_6 has exhibited promising prospect.The stability of penicillin G is crucial for developing a green ionic liquid-based extraction technology.In this work,the stability of penicillin G in[Bmim]PF_6 was systematically investigated.The results showed the stability of penicillin G was significantly influenced by pH and temperature.It tended to be more stable when pH value increased from 1.5 to 4.0 and the temperature gradually decreased.The half-life(t_(1/2))of penicillin G in[Bmim]PF_6 was 17.7 h in the optimal technological condition(pH 2.0 and 10°C),which is enough for the requirement of extraction technology.The reaction of penicillin G in[Bmim]PF_6 followed the first order kinetics in the pH range 2.0–4.0.Three isomers of penicillin G were found through rearrangement at pH 2.0,and their structures were not affected by temperature.     

固载化离子液体催化碳酸乙烯酯水解制备乙二醇

采用溶胶-凝胶法制备了以SiO2为载体的固载化离子液体催化剂,并将其首次用于催化碳酸乙烯酯(EC)水解制备乙二醇(EG)的反应. 结果表明,固载化碱性离子液体S-[bpim][HCO3]对碳酸乙烯酯水解制EG反应具有良好的催化活性和EG选择性,克服了非均相催化剂活性不高与均相催化剂难以分离的不足. 在催化剂浓度为0.0511 g/mL、温度140℃、压力0.4 MPa及EC/H2O=1:2(摩尔比)、反应时间3 h的条件下,EC转化率达99.7%,EG选择性为100%. 该催化剂在循环使用5次后,EC转化率无明显下降,EG的选择性始终接近100%.     

乙二醇胺化合成哌嗪催化剂及工艺

在固定床反应器中,以乙二醇为原料,胺化合成哌嗪。对催化剂活性组分及载体进行了筛选,并系统地考察了反应温度、压力、乙二醇空速、氨醇物质的量之比和氢醇物质的量之比等对胺化反应的影响。结果表明,Ni-Cu复合金属是合成哌嗪较好的活性组分,丝光沸石作为载体哌嗪选择性较高。在反应温度230℃,压力10 MPa,乙二醇液时空速0.2 h~(-1),氨醇物质的量之比为30,氢醇物质的量之比为1的条件下,乙二醇胺化合成哌嗪反应性能较好,乙二醇转化率为42%,哌嗪选择性为75%。     

离子液体[Bmim]Cl-CrCl2促进高炔丙醇化合物的合成

离子液体[bmim]Cl-CrCl2促进下,醛酮与炔丙基溴发生Barbier型反应合成了高炔丙醇化舍物,考察了反应条件和不同底物对炔丙基化反应的影响.结果表明,在[bmim]Cl与CrCl2物质的量比为1:2,醛酮、炔丙基溴和离子液体物质的量比为2:3:2,反应温度为50℃和反应时间为1～5 h的条件下,一系列醛酮能与...     

[Bmim]Cl-xAlCl_3催化合成十二烷基苯

采用AlCl3和[Bmim]Cl不同摩尔比的[Bmim]C1-xA1C13离子液体为催化剂,研究了不同条件下1-十二烯与苯的烷基化反应。实验结果表明,以A1Cl3和[Bmim]Cl的摩尔比为2.0([Bmim]Cl-2A1C13)的离子液体为催化剂,在反应温度25℃、反应时间30 min,苯、烯及离子液体的摩尔比为5︰1︰0.03的条件下,正十二烯的转化率可达98.32%,2-LAB的选择性可达36.76%。离子液体和产物可形成易于分离的双液相,简化了催化剂与产物的分离操作。     

乙酰乙酸乙酯金属配合物催化丁二酸二甲酯和碳酸乙烯酯的耦合反应

研究了乙酰乙酸乙酯金属配合物催化碳酸乙烯酯(EC)和丁二酸二甲酯(DMSu)同时合成聚丁二酸乙二醇酯(PES)预聚体和碳酸二甲酯(DMC)耦合反应新工艺。结果表明,以乙酰乙酸乙酯锌为催化剂,反应温度205～215℃,n(乙酰乙酸乙酯锌)/n(EC+DMSu)=0.001,n(EC)/n(DMSu)=4,反应时间1 h时,DMC收率为52.3%,PES的特性黏度为0.117 4 dL/g。     

固载化离子液体催化环氧乙烷和二氧化碳合成碳酸乙烯酯

用溴化1-羟乙基-3-乙烯基咪唑、甲基丙烯酸钠、丙烯酸羟乙酯、苯乙烯4种单体共聚合成了高分子离子液体催化剂,表征了其结构. 将该催化剂固载到分子筛上制成固体颗粒催化剂,催化环氧乙烷(EO)与CO2合成碳酸乙烯酯(EC)的反应,考察了反应时间、温度、压力、催化剂用量对EO转化率及生成EC选择性的影响. 结果表明,在反应时间4 h、温度403.15 K、压力2.5 MPa、催化剂与环氧乙烷质量比9%的条件下,EO转化率为95%, EC选择性为98%,催化剂在循环使用10次后,EO转化率无明显下降,EC选择性接近100%. 该反应为一级反应,动力学方程为r=-dCEO/dt=9.872×104e-52.00/(RT)CEO.     

强酸性阳离子交换树脂催化合成苯乙酮环乙二缩酮的研究

在强酸性阳离子交换树脂催化剂存在下,以苯乙酮、乙二醇为原料合成苯乙酮环乙二缩酮,分别研究了反应温度,反应时间,原料配比,催化剂用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成苯乙酮环乙二缩酮的最佳工艺条件是:反应温度为95℃,反应时间2.5 h,n(苯乙酮)∶n(乙二醇)=0.2∶0.28;强酸性阳离子交换树脂用量为1.5 g;带水剂环己烷为40 mL(苯乙酮为0.2 mol的情况下)。苯乙酮环乙二缩酮的收率可达到96.25%,产品纯度99.5%以上。催化剂不经处理可循环使用多次。该催化剂具有价廉易得、催化活性好、不腐蚀设备、无环境污染等优点。     

La/SO_4~(2-)/C催化合成环缩酮

以固体超强酸La/SO42-/C为多相催化剂,通过环己酮和乙二醇反应合成了环己酮缩乙二醇,探讨La/SO42-/C对缩酮反应的催化活性,较系统地研究了酮醇摩尔比,催化剂用量,反应时间诸因素对产品收率的影响。实验表明:La/SO42-/C是合成环己酮缩乙二醇的良好催化剂,在酮醇摩尔比为1∶1.5,催化剂用量为反应物料总质量的1.5%,环己烷为带水剂,反应时间60m in的条件下,环己酮缩乙二醇的收率可达90.6%。     

离子液体催化合成2-(4-乙基苯甲酰基)苯甲酸

研究了离子液体催化合成2-(4-乙基苯甲酰基)苯甲酸。并对离子液体中[Bmim]Cl与三氯化铝的摩尔比、原料配比、反应温度和反应时间等工艺条件进行了考察。较优工艺条件为:n(AlCl3)∶n([Bmim]Cl)=1∶3,n(离子液体)∶n(邻苯二甲酸酐)∶n(乙苯)=1∶1∶1,反应温度为50℃,反应时间为4h,在此条件下,[Bmim]Cl-AlCl3催化邻苯二甲酸酐的转化率可达100%,目标产物2-(4-乙基苯甲酰基)苯甲酸的选择性达97.14%,可避免使用有机溶剂。     

乙二醇乙酸酯合成的研究

研究了以乙二醇和乙酸为原料，在三氯化铁催化剂和醋酸丁酯共沸脱水剂作用下合成乙二醇单乙酸酯工艺。结果表明：n(乙二醇)：n(乙酸)=2，脱水剂用量15％(占原料总量)，催化剂用量0．6％(占原料总量)，乙二醇乙酸酯的产率达82%。