Preparation of Ni(HCO_3)_2 and its catalytic performance in synthesis of benzoin ethyl ether

Ni（HCO3）2 with unique phase and high crystallinity was synthesized with urea hydrolysis. The as-prepared samples were well characterized in detail. N2 adsorption and desorption result manifests a high surface area of 99.03 m2/g with a pore size of 7.8 nm. Scanning electron microscopy （SEM） and particle size distribution reveal that the diameters of the formed pellets are uniform. Thermogravimetry （TG） analysis result shows that 500 ℃ could be the appropriate temperature for converting Ni（HCO3）2 precursors into NiO via a thermal decomposition process. CO2 and NH3 temperature-programmed desorption results show that Ni（HCO3）2 has explicit acid-base sites. Transmission electron microscopy （TEM） results vividly indicate that the pellets are aggregated by hexagonal platelets and possess porous structures. Ni（HCO3）2 can efficiently catalyze the one-step synthesis of benzoin ethyl ether from benzaldehyde and ethanol, with the conversion ofbenzaldehyde up to 57.5% and nearly 100% selectivity of benzoin ethyl ether.

Synthesis of dimethyl ether from methane mediated by HBr

Dimethyl ether （DME） was synthesized from methane through a two-step process, in which CH3Br was prepared from the oxidative bromination reaction of methane in the presence of HBr and oxygen over a Rh-SiO2 catalyst and then, in the second step, CH3Br was hydrolyzed to DME over a silica supported metal chloride catalyst. 12 mol%ZnCl2/SiO2 catalyst was found to be the most active, but it deactivated because of Cl- losing.

Hybrid Process of Reactive Distillation and Pervaporation for the Production of Tert-amyl Ethyl Ether

In this study, a reactive distillation column in which chemical reaction and separation occur simultaneously is applied for the synthesis of tert-amyl ethyl ether （TAEE） from ethanol （EtOH） and tert-amyl alcohol （TAA）. Pervaporation, an efficient membrane separation technique, is integrated with the reactive distillation for enhancing the efficiency of TAEE production. A user-defined Fortran subroutine of a pervaporation unit is developed, allowing the design and simulation of the hybrid process of reactive distillation and pervaporation in Aspen Plus simulator. The performance of such a hybrid process is analyzed and the results indicate that the integration of the reactive distillation with the pervaporation increases the conversion of TAA and the purity of TAEE product, compared with the conventional reactive distillation.

Superior gallstone dissolubility and safety of tert-amyl ethyl ether over methyl-tertiary butyl ether

BACKGROUND The use of methyl-tertiary butyl ether(MTBE)to dissolve gallstones has been limited due to concerns over its toxicity and the widespread recognition of the safety of laparoscopic cholecystectomy.The adverse effects of MTBE are largely attributed to its low boiling point,resulting in a tendency to evaporate.Therefore,if there is a material with a higher boiling point and similar or higher dissolubility than MTBE,it is expected to be an attractive alternative to MTBE.AIM To determine whether tert-amyl ethyl ether(TAEE),an MTBE analogue with a relatively higher boiling point(102°C),could be used as an alternative to MTBE in terms of gallstone dissolubility and toxicity.METHODS The in vitro dissolubility of MTBE and TAEE was determined by measuring the dry weights of human gallstones at predetermined time intervals after placing them in glass containers with either of the two solvents.The in vivo dissolubility was determined by comparing the weights of solvent-treated gallstones and control(dimethyl sulfoxide)-treated gallstones,after the direct infusion of each solvent into the gallbladder in both hamster models with cholesterol and pigmented gallstones.RESULTS The in vitro results demonstrated a 24 h TAEE-dissolubility of 76.7%,56.5%and 38.75%for cholesterol,mixed,and pigmented gallstones,respectively,which represented a 1.2-,1.4-,and 1.3-fold increase in dissolubility compared to that of MTBE.In the in vitro experiment,the 24 h-dissolubility of TAEE was 71.7%and 63.0%for cholesterol and pigmented gallstones,respectively,which represented a 1.4-and 1.9-fold increase in dissolubility compared to that of MTBE.In addition,the results of the cell viability assay and western blot analysis indicated that TAEE had a lower toxicity towards gallbladder epithelial cells than MTBE.CONCLUSION We demonstrated that TAEE has higher gallstone dissolubility properties and safety than those of MTBE.As such,TAEE could present an attractive alternative to MTBE if our findings regarding its efficacy and safety can be consistently reproduced in further subclinical and clinical studies.

Optimizing the Synthesis of Ethyl tert-Butyl Ether in Continuous Catalytic Distillation Column Using New Ion Exchange Resin Catalyst

Liquid phase synthesis of one of the important fuel oxygenate, ethyl tert-butyl ether （ETBE）, from etha-nol and tert-butyl alcohol （TBA） has been studied in catalytic distillation column （CDC） using ion exchange resin catalyst CT-145H. A packed CDC of 1.2 m height and 50 mm diameter with indigenously developed reactive sec-tion packing was used to generate experimental data. Effect of different key variables on product purity in distillate, was investigated to find the optimum operating conditions for ETBE synthesis. The optimum conditions for 0.2 kg·s-1 of ethanol feed were found：reboiler duty of 375 W, molar feed ratio of 1︰1.3 of reactants, and reflux ratio of 7. Concentration profiles for each component along each column section at optimum conditions were also drawn. Neither output nor input multiplicity was observed at experimental conditions.

Preparation of Ethylene Glycol Monoethyl Ether Acetate Using a Tubular Reactor

Ethylene glycol monoethyl ether acetate (EGEA), an excellent solvent, is prepared with ethylene oxide (EO) and ethyl acetate (EA) in a tubular reactor under suitable reaction condition. The single circulation yield can reach 81%. This technology is not only safe but also makes it possible to continuously produce EGEA in industry,with low content of high boiling point by-products.

养心草提取物抗肺癌活性部位筛选

目的筛选养心草抗肺癌活性部位。方法运用系统溶剂法制备养心草各提取部位;体外培养肝癌A549细胞,采用MTT法检测细胞株半数抑制浓度(IC50),以IC50作为评价指标,初步筛选出养心草抗肿瘤的有效部位。同时,建立肺癌LLC细胞移植瘤小鼠模型,通过观察肿瘤体积、小鼠体质量、脏器指数及瘤体质量的变化,对养心草的抗肿瘤效果进行评价养心草石油醚部位及乙酸乙酯部位的体内抗肺癌作用。结果MTT实验结果表明养心草不同提取部位中石油醚部位和乙酸乙酯部位对肺癌A549细胞的增殖显示较强的抑制作用;体内小鼠肺癌LLC细胞移植瘤实验表明石油醚部位和乙酸乙酯部位可明显抑制小鼠肿瘤的生长(P<0.05),且具有剂量依赖性,并对鼠体质量及脏器指数未产生显著影响(P>0.05)。结论养心草的石油醚部位和乙酸乙酯部位是其抗肺癌的有效部位。

榆干玉蕈子实体及其提取物的免疫调节作用

为研究榆干玉蕈(Hypsizygusulmarius)子实体粉末及提取物对小鼠的免疫调节作用,分别采用榆干玉蕈子实体粉末(高、低剂量分别为1.2、0.3g·kg^(-1))、石油醚提取物(高、低剂量分别为1.392、0.348mg·kg^(-1))、乙酸乙酯提取物(高、低剂量分别为3.306、0.826 mg·kg^(-1))、水提取物(高、低剂量分别为28.78、7.19 mg·kg^(-1))灌胃大黄水煎液建立的模型小鼠,测定其体质量、脾脏指数及血清中白细胞介素2(interleukin-2,IL-2)、白细胞介素6(interleukin-6,IL-6)、免疫球蛋白M(immunoglobulin M,IgM)、干扰素γ(interferon-γ,IFN-γ)、D-木糖(D-xylose)、白蛋白(albumin,ALB)、胰脂肪酶(pancrelipase,PL)含量,采用苏木素-伊红染色观察小鼠脾脏组织显微结构,采用RT-qPCR法检测维生素D结合蛋白(D binding protein,DBP)和紧密连接蛋白(occludin,OCLN)的基因表达情况,并采用Westernblotting方法检测DBP和OCLN蛋白表达情况。结果表明:与模型组相比,第14天,各给药组小鼠体质量均显著增加。粉末高剂量组脾脏指数显著增加。所有给药组D-xylose、IFN-γ、ALB、IL-2、IgM、PL含量均显著增加,IL-6含量显著降低。各给药高剂量组DBP基因相对表达量显著升高,所有低剂量组显著降低;粉末低剂量组、石油醚提取物高和低剂量组、水提物高和低剂量组的OCLN基因相对表达量均显著升高。各给药组DBP和OCLN的蛋白表达量均显著升高。榆干玉蕈子实体及各提取物均通过免疫调节发挥作用,研究结果可为榆干玉蕈进一步开发利用提供参考。

微反应器中羰基锰催化三臂星型聚合物的制备

构建了微尺度下光诱导阳离子聚合反应平台,开发了羰基锰高效催化制备三臂星型聚乙烯基乙醚(PEVE)的新方法。利用GPC,^(1)H NMR等方法考察了微反应器的聚合效果,探究了微尺度下阳离子聚合规律,同时拓展了单体的种类。实验结果表明,在微尺度下利用光诱导阳离子聚合,反应条件温和,聚合过程可控,所得PEVE分子量调节范围宽、分子量分布(MWD)窄,解决了传统工艺中存在的反应条件苛刻、能耗高、产品质量可控性差等问题。在微尺度反应平台上,还利用羰基锰催化体系成功合成了MWD窄的聚甲基丙烯酸甲酯,以及分子量为14 000~35 000、MWD为1.37~1.48的三臂星型聚甲基丙烯酸甲酯-嵌段-聚甲基丙烯酸十二烷基酯。

酱香型酒糟中难挥发性化学成分的研究

为了研究酱香型酒糟中难挥发性化学成分,实验以75%乙醇提取茅台酒糟,利用硅胶、ODS、Sephadex LH-20等柱色谱及制备型HPLC对酒糟石油醚、乙酸乙酯萃取部位进行分离纯化,得到21个化合物。化合物经ESI-MS和NMR波谱分析技术鉴定,分别鉴定为十五烷酸(1)、十六烷酸(2)、反式-2-癸烯酸(3)、十八酸正壬酯(4)、十八酸乙酯(5)、亚油酸乙酯(6)、十二烷酸(7)、1,3-二辛酰基-2-亚油酰基甘油(8)、环(苯丙氨酸-脯氨酸)(9)、环(脯氨酸-亮氨酸)(10)、3,6-双(2-甲基丙基)-2,5-哌嗪二酮(11)、4-羟基苯乙醇(12)、2,4-二羟基苯甲酸(13)、豆甾醇(14)、2-呋喃甲酸(15)、缬氨酸(16)、L-丙氨酰-L-脯氨酸(17)、二氢槲皮素(18)、5,7,3',4'-四羟基二氢黄酮(19)、槲皮素(20)、柚皮素(21)。化合物1~21为首次从酒糟中分离得到。

醚的制备改进实验——二苯甲基乙基醚

醚的制备是有机化学实验的一个重要内容,教材中对应的实验内容是甲基叔丁基醚和正丁醚的制备。通过该部分学习对于深刻理解醇的化学性质和亲核取代反应的SN1、SN2两种机制具有重要的作用。然而,教材中基于SN1机理的甲基叔丁基醚制备实验仍存在需化学计量硫酸催化剂、反应进程不易跟踪、产物难以纯化且产率低等问题。本实验以无水三氯化铁作为催化剂,使用二苯甲醇与乙醇反应,反应混合物经洗涤除杂操作后,可以以88%–90%收率,95%–97%纯度得到二苯甲基乙基醚产物。本实验与现有教材中甲基叔丁基醚制备的反应机理和教学要点一致,但催化剂用量显著降低、产物分离纯化步骤显著减少,产物收率明显提高。本实验有助于学生深入理解碳正离子中间体的性质、有机化学中的路易斯酸碱理论及其催化反应和SN1机理等基本理论,有助于培养学生绿色化学理念。

2-氯乙基乙基醚的无溶剂合成

对2-氯乙基乙基醚的合成工艺进行了无溶剂合成改进。以三乙胺为催化剂,乙二醇单乙醚与二氯亚砜发生氯代反应合成了2-氯乙基乙基醚,产物经饱和碳酸钠溶液碱洗、饱和氯化钠溶液水洗、无水硫酸钠干燥,得到2-氯乙基乙基醚,采用^(1)HNMR和GC-MS对产物结构进行了表征。采用单因素实验考察了投料物质的量比、反应温度和反应时间对产物GC纯度和收率的影响。优化后2-氯乙基乙基醚的合成工艺为n(乙二醇单乙醚)∶n(二氯亚砜)∶n(三乙胺)=1.0∶1.3∶0.3、反应温度为70℃、反应时间为4h。在该工艺下经公斤级中试放大,产品的收率可达90.2%以上、GC纯度达到99.4%以上、含量达到99.2%以上。

β-萘乙醚的微波合成研究

研究了以β 萘酚、无水乙醇为原料,浓硫酸为催化剂,采用微波辐射方法合成β 萘乙醚,并探索了反应条件对产物产率的影响。实验结果表明,在反应物用量β 萘酚3.6g(0.025mol),无水乙醇30mL,浓硫酸7mL,微波辐射功率260W,微波辐射时间40min条件下反应,产率可达71%以上。与常规加热合成方法比较,本方法反应时间大大缩短(由6h缩至40min),产率较高(从60%增至71%)。

微波辐射无溶剂氯化铜催化合成β-萘乙醚

以CuCl_2·2H_2O为催化剂,采用微波辐射无溶剂催化合成β-萘乙醚,探索了不同反应条件对产率的影响。实验结果表明,该方法具有反应时间短、产率高(80％)、无污染等特点。

微波辐射硫酸铝催化合成β-萘乙醚

研究了以β-萘酚和乙醇为原料,在硫酸铝催化下应用微波辐射技术合成β-萘乙醚。运用正交实验方法确定了最佳合成条件:β-萘酚与乙醇摩尔比1∶5.5、催化剂与反应物质量比1∶5.95、反应温度100℃、反应时间20 min。在此最佳条件下,产物收率可达70%以上。采用熔点法和红外光谱法对产品进行了表征。

牡丹皮乙醇提取物中的1个新芍药苷衍生物

目的:对牡丹皮中的芍药苷类化学成分进行研究。方法:利用萃取,硅胶柱色谱,中压反相柱色谱和HPLC等进行分离制备,利用IR,MS及NMR技术进行确证和鉴定。结果:从牡丹皮乙醇提取物中制备并鉴定了9个芍药苷类化合物,其中1个为新化合物。结论:新化合物结构鉴定为芍药苷4乙基醚,并通过模拟实验证明可能为提取过程中产生的人工产物。

二乙二醇甲乙醚的合成

以二乙二醇单乙醚(C6H14O3)和氢氧化钠为原料,在n(NaOH):n(C6H14O3)=1.5:1.0,苯为带水剂的条件下,先合成了二乙二醇单乙醚单钠盐,然后使CH3Cl与二乙二醇单乙醚单钠盐进行Williamson反应合成了二乙二醇甲乙醚(DEGMEE)。研究了反应温度、反应时间及CH3Cl/C6H14O3(摩尔比)对DEGMEE收率的影响。用气相色谱法分析了产物的纯度,用FT-IR和1HNMR的方法表征了产物结构。结果表明:在反应温度80℃,CH3Cl通入时间4.0h,n(CH3Cl):n(C6H14O3)=1.40:1的条件下,DEGMEE的收率大于90%。

乙基叔丁基醚合成反应动力学

乙基叔丁基醚一般由乙醇和异丁烯合成，以阳离子交换树脂为催化剂．研究了外扩散阻力为零时的合成反应宏观动力学模型．其本征动力学采用广义Langmuir-Hinshelwood速率方程，将反应速率用液相活度系数关联．内扩散用广义Maxwell-Stefen方程描述，以组分的化学位梯度为扩散推动力．本模型较好地描述了非理想反应物系统的吸附特性和扩散过程．用文献中的实验数据对模型作了检验.

乙基叔丁基醚的催化反应与渗透蒸发膜分离耦合法的合成

以乙醇（ＥｔＯＨ）及叔丁醇（ＴＢＡ）为原料，用催化反应与渗透蒸发膜分离耦合的方法，以强酸性阳离子交换树脂Ａｍｂｅｒｌｙｓｔ１５为催化剂，合成了乙基叔丁基醚（ＥＴＢＥ）。研究考察了水－醇体系中水的渗透速率及膜的选择性，讨论了渗透蒸发膜分离耦合与否对其反应结果的影响。在考虑了试验条件下ＴＢＡ分解为水与异丁烯（ＩＢ）而引起的体积减少、水的吸附对催化剂活性的阻害效应以及水的渗透通量等因素的基础上，得出了一数学模型。试验结果与模型计算值比较一致。

山荷叶中木脂素成分的研究

从陕西产山荷叶(Diphylleia sinensis Li.)根茎中分得9个木脂素和1个黄酮化合物,通过光谱分析证明化合物Ⅸ为新木脂素,即苦鬼臼素-1-乙基醚(picropodophyllin-1-ethyl ether),其它化合物分别为鬼臼毒素(podophyllotoxin,Ⅰ)、异苦鬼臼酮(isopicropodophyllone,Ⅱ)、去氢鬼臼毒素(dehydropodophyllotoxin,Ⅲ)、山荷叶素(diphyllin,Ⅳ)、苦鬼臼素(picropodophyllin,Ⅴ)、鬼臼酯酮(podophyllotoxone,Ⅵ)、4′-去甲基鬼臼毒素(4′-demethylpodophyllotoxin,Ⅶ)、苦鬼臼素葡萄糖甙(picropodophyllin slucoside,Ⅷ)和山奈酚(kaempferol,Ⅹ)。其中化合物Ⅱ,Ⅵ,Ⅶ和Ⅷ为首次从山荷叶属植物中分得。