离子液体协同固体酸催化花生壳制备乙酰丙酸的研究

以离子液体氯化1-丁基-3-甲基咪唑鎓([Bmim]Cl)为溶剂,以6种S2O82-/MxOy型固体超强酸为催化剂,将微波预处理后的花生壳水解,制备乙酰丙酸。研究表明,S2O82-/Zr O2-Al2O3-Si O2固体酸的催化效果最佳,进一步考察了反应时间、反应温度、固体酸用量、水含量对乙酰丙酸产率的影响。由响应面法(RSM)建立的二次回归模型得到优化水解工艺条件,即:在固体酸用量为5.1(wt)%条件下于160℃反应51min,乙酰丙酸产率可达到78.3%。固体酸再生重复使用效果良好。     

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.     

离子液体接枝的有机介孔催化剂的制备及催化碳酸丙烯酯水解反应

以甲基咪唑和3-氯-1丙醇为原料合成离子液体（1-羟丙基-3-甲基咪唑四氟硼酸盐,NpmimBF4）,并将其接枝固载到有机介孔材料（FDU-15）上,合成制备了有机介孔催化剂（NpmimBF4- FDU）。采用热重、Ｘ射线衍射、红外光谱及透射电子显微镜等技术手段对催化剂结构进行了表征,并考察了催化剂在碳酸丙烯酯（PC）水解反应中的催化性能,结果表明,该催化体系在常压下能有效催化碳酸丙烯酯水解生成1,2-丙二醇。在催化剂的质量分数为4%、温度80 ℃、反应时间2 h的条件下,1,2-丙二醇的产率大于99%。经简单分离后催化剂可重复使用5次,但活性变化较大。同时对催化碳酸丙烯酯水解生成1,2-丙二醇（PG）的反应机理进行了初步探讨。     

Electrochemical Reduction of Benzoylformic Acid in Ionic Liquid

Ionic Hquids possess a number of unique properties that makethem ideal electrolytes. Electrochical reduction of benzoyl-formic acid in room temperature ionic liquids as reaction media could be conducted with excellent performances without any ad-ditional supporting electrolyte. Electrolysis at glassy carbon electrode results in the formation of mandelic acid in 91% yield. And the electrochemical behavior of benzoylformic acid was investigated with the technique of cyclic voltammetry.     

羧基功能化离子液体催化合成1,5-苯并二氮衍生物

在无溶剂条件下,以邻苯二胺和丙酮为原料,羧基功能化离子液体CmmimBF_4(IL)为催化剂,合成了1,5-苯并二氮衍生物(2),其结构经~1H NMR和IR表征.在IL用量为10 mol%,于40 ℃反应1.5 h的条件下,2的产率达93%.IL无需再生处理,可连续循环使用5次,且活性无明显下降.     

The Influence of Carbon Nature on the Catalytic Performance of Ru/C in Levulinic Acid Hydrogenation with Internal Hydrogen Source

The influence of the nature of carbon materials used as a support for Ru/C catalysts on levulinic acid hydrogenation with formic acid as a hydrogen source toward gamma-valerolactone was investigated. It has been shown that the physicochemical properties of carbon strongly affect the catalytic activity of Ru catalysts. The relationship between the hydrogen mobility, strength of hydrogen adsorption, and catalytic performance was established. The catalyst possessing the highest number of defects, stimulating metal support interaction, exhibited the highest activity. The effect of the catalyst grain size was also studied. It was shown that the decrease in the grain size resulted in the formation of smaller Ru crystallites on the catalyst surface, which facilitates the activity.     

离子液体固定相离子色谱法测定淀粉中的顺反式丁烯二酸

采用新型聚合离子液体嫁接硅胶多模式色谱固定相(Sil-pC11C1Im柱,4.6 mm×150 mm),建立了淀粉中顺反式丁烯二酸的新型离子色谱测定方法。实验通过考察流动相的pH值和无机盐浓度对分离检测顺、反丁烯二酸的影响,得到优化的色谱条件:流动相为甲醇-10 mmol/L磷酸二氢钠(体积比为5∶95,pH7.0),流速为1.0 mL/min,检测波长为215 nm,进样量为15μL。在优化条件下,顺反式丁烯二酸的线性范围为0.1~2.0 mg/L,回收率为93.0%~99.6%,相对标准偏差(RSD,n=5)为1.1%~7.6%,检出限(S/N=3)为0.02 mg/L,定量下限(S/N=10)为0.66 mg/kg。该方法样品前处理简单、快速,定性定量检测效果良好。     

酸性功能化离子液体催化合成叶青素

以含磺酸基离子液体1-(4-磺酸基)丁基-3-甲基咪唑四氟硼酸盐([4-sulfbmim][BF₄])为酸性催化剂,由乙缩醛和苯甲醇合成了叶青素。 采用正交实验方法考察了合成条件的影响,固定反应温度为20 ℃条件下,确定优化合成条件为：n(苯甲醇)∶n(乙缩醛)=1∶8,反应时间60 min,催化剂用量为每摩尔苯甲醇4 g,产率为92.2%。 与H₂SO₄催化剂相比[4-sulfbmim][BF₄]的催化活性相对较弱,但综合效果优于H₂SO₄。 [4-sulfbmim][BF₄]循环使用6次,催化活性基本不变。     

Synthesis of Tetrahydrofuran and Tetrahydropyran Derivatives Catalyzed by Tungstophosphoric Acid in Ionic Liquid

Synthesis of tetrahydrofuran and tetrahydropyran derivatives catalyzed by tungstophosphoric acid （H3PW12040） were conveniently performed with high yield from the corresponding unsaturated alcohols in ionic liquid. Sufuric acid （H2SO4）, trifluoromathanesulfonic acid （TfOH） and p-toluenesulfonic acid （TsOH） were also explored for preparing these products in ionic liquid. The catalysts and ionic liquid can be easily recovered and reused.     

己内酰胺三氟甲磺酸离子液体中甲苯的区域选择性硝化

以三氟甲磺酸和己内酰胺为原料制备了一种新型离子液体己内酰胺三氟甲磺酸([CP]OTf),用1HNMR、FTIR对其结构进行了表征。并把[CP]OTf作为催化剂和溶剂,用于催化甲苯的硝化反应。借助气相色谱研究了[CP]OTf的用量、硝化温度、反应时间、硝酸浓度和离子液体的重复使用等因素对甲苯硝化反应区域选择性和产率的影响。结果表明：在反应温度55℃,反应时间6h,甲苯与95%浓硝酸的摩尔比为1：1,离子液体用量占甲苯摩尔数的15%时,产物中邻对位硝基甲苯摩尔比为1.12,较浓硫酸催化硝化的相应值(1.67)显著降低,硝基甲苯的产率达到78.41%,[CP]OTf表现出了优良的催化活性和对位选择性。[CP]OTf) 重复使用5次,其催化活性及对位选择性变化很小。     

脯氨酸离子液体催化Knoevenagel缩合反应(英文)

改进了1-丁基-3-甲基咪唑L-脯氨酸([bmim][Pro])功能化离子液体的合成路线,并将该离子液体用于催化含活泼亚甲基化合物与醛或酮的Knoevenagel缩合反应.在水介质中,室温下,该离子液体可快速催化上述Knoevenagel缩合反应,并选择性生成α,β-不饱和羰基化合物且分离收率可达到88%～97%.该脯氨酸离子液体循环重复使用6次后,催化活性没有明显的下降.此外,初步探讨了其催化过程机理.     

离子液体中Lewis酸催化葡萄糖和果糖脱水制备5-羟甲基呋喃甲醛

在离子液体中采用不同的Lewis酸催化葡萄糖和果糖脱水制备5-羟甲基呋喃甲醛(5-HMF).结果表明,CrCln和SnCln均可高效催化葡萄糖转化为5-HMF.另外,Lewis酸的酸性越强,其催化果糖转化为5-HMF的产率越高.镧系金属氯化物在反应中表现出较好的催化活性和产物选择性.同时还研究了离子液体结构对催化反应的...     

溴化锌-离子液体复合催化体系高效催化合成环状碳酸酯

随着全球“温室效应”和能源危机的加剧,用CO2作为某些化学品的Cl起始原料,既经济、安全,又能降低CO2对环境的危害,由于CO2的性质极不活泼,在固定CO2的反应中最典型的一个催化过程就是利用CO2和环氧化合物通过环加成反应合成环状碳酸酯：     

A Catalyst and Solvent Free Route for the Synthesis of N-Substituted Pyrrolidones from Levulinic Acid

An efficient, metal-free, catalyst-free and solvent-free methodology for the reductive amination of levulinic acid with different anilines has been developed using HBpin as the reducing reagent. This protocol offers an excellent method to avoid solvents and added catalysts on the synthesis of different kinds of N-substituted pyrrolidones under metal free conditions. It is also the first report for the synthesis of different pyrrolidones by solvent-free as well as catalyst-free methods. The proposed mechanism for the formation of pyrrolidone has been supported by DFT calculations and control experiments.     

磷钨酸离子液体催化合成N-苯基邻苯二甲酰亚胺的研究

以邻苯二甲酸酐为原料,以磷钨酸离子液体为催化剂合成了N-苯基邻苯二甲酰亚胺。通过对溶剂、反应温度、催化剂用量的研究,探索了磷钨酸离子液体催化反应条件和催化剂循环使用效果。结果表明,催化合成的最佳反应条件是:甲苯作为溶剂,催化剂用量为0.20 mmol,反应温度为100℃。催化剂循环使用6次后催化剂损失率小于0.01%。该方法实现了N-苯基邻苯二甲酰亚胺的绿色合成。     

离子液体催化剂用于煤焦化苯深度脱硫制无硫苯

从扩大有机合成用苯的需求出发,采用研制的离子液体催化剂考察了煤焦化苯深度脱硫制无硫苯的过程。结果表明：N-甲基咪唑硫酸氢盐[Hmim][HSO₄]离子液体催化剂脱噻吩效果与其酸函数值有关。本文采用Hammett指示剂测定离子液体的酸函数H₀,并得出：在-4至-12的范围,离子液体催化剂可以使煤焦化苯噻吩脱至0. 5mg/L以下。与固体酸催化机理相似,酸量和酸强度一定的离子液体催化剂通过Friedel-Crafts反应形成烷基噻吩等,与苯的物性拉开距离,对苯的分离精制是必不可少的,但是过多、过强的[Hmim][HSO₄]酸值也更有利于苯-噻吩-烯烃共聚合等副反应的发生,从而影响离子液体催化剂重复使用的寿命。本研究利用煤焦化苯脱硫反应形成的噻吩衍生物作为提供电荷流通的聚合物,将反复使用后性能不佳的离子液体成分等作为“受电子型”和“给电子型”的掺杂剂,进行导电（抗静电）材料的制备。结果显示：对煤焦化苯脱硫形成的噻吩衍生物等可以用于掺杂导电材料的试制。     

Oxidative Conversion of Glucose to Formic Acid as a Renewable Hydrogen Source Using an Abundant Solid Base Catalyst

Formic acid is one of the most desirable liquid hydrogen carriers. The selective production of formic acid from monosaccharides in water under mild reaction conditions using solid catalysts was investigated. Calcium oxide, an abundant solid base catalyst available from seashell or limestone by thermal decomposition, was found to be the most active of the simple oxides tested, with formic acid yields of 50 % and 66 % from glucose and xylose, respectively, in 1.4 % H₂O₂ aqueous solution at 343 K for 30 min. The main reaction pathway is a sequential formation of formic acid from glucose by C−C bond cleavage involving aldehyde groups in the acyclic form. The reaction also involves base-catalyzed aldose-ketose isomerization and retroaldol reaction, resulting in the formation of fructose and trioses including glyceraldehyde and dihydroxyacetone. These intermediates were further decomposed into formic acid or glycolic acid. The catalytic activity remained unchanged for further reuse by a simple post-calcination.     

离子液体协同固体超强酸催化花生壳制备乙酰丙酸

以离子液体氯化1-丁基-3-甲基咪唑鎓([Bmim]Cl)为溶剂,以6种S2O82-/MxOy型固体超强酸为催化剂,将微波预处理后的花生壳水解,制备乙酰丙酸。研究表明,S2O82-/Zr O2-Al2O3-Si O2固体酸的催化效果最佳,进一步考察了反应时间、反应温度、固体酸用量、水含量对乙酰丙酸产率的影响。由响应面法(RSM)建立的二次回归模型得到优化水解工艺条件,即:在固体酸用量为5.1(wt)%条件下于160℃反应51min,乙酰丙酸产率可达到78.3%。固体酸再生重复使用效果良好。     

微波促进酸性离子液体催化水杨酸酯化

用自制的硫酸氢1-甲基-3-(3-磺酸基丙基)咪唑([MIMPS]HSO4)酸性离子液体作为水杨酸与醇的酯化反应催化剂,考察了温度、时间、物料配比和离子液体用量等因素对酯化反应的影响,优化的最佳反应条件为: 微波辐射时间20 min,反应温度95 ℃,醇与酸摩尔比3∶1(水杨酸的量为0.02 mol),[MIMPS]HSO4用量10 mmol,水杨酸甲酯的产率和选择性分别为91.9%和99.0%。 离子液体回收循环使用4次,催化效率不变。 与热催化酯化反应相比,微波辐射可缩短反应时间;水杨酸与不同碳链醇的酯化产率随着碳链的增加而降低,同碳链的伯醇酯化率比仲醇高。     

Efficient Reduction of CO2 into Formic Acid on a Lead or Tin Electrode using an Ionic Liquid Catholyte Mixture

Highly efficient electrochemical reduction of CO₂ into value‐added chemicals using cheap and easily prepared electrodes is environmentally and economically compelling. The first work on the electrocatalytic reduction of CO₂ in ternary electrolytes containing ionic liquid, organic solvent, and H₂O is described. Addition of a small amount of H₂O to an ionic liquid/acetonitrile electrolyte mixture significantly enhanced the efficiency of the electrochemical reduction of CO₂ into formic acid (HCOOH) on a Pb or Sn electrode, and the efficiency was extremely high using an ionic liquid/acetonitrile/H₂O ternary mixture. The partial current density for HCOOH reached 37.6 mA cm^?2 at a Faradaic efficiency of 91.6 %, which is much higher than all values reported to date for this reaction, including those using homogeneous and noble metal electrocatalysts. The reasons for such high efficiency were investigated using controlled experiments.