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1.
环氧丙烷和甲醇在MgO上合成1-甲氧基-2-丙醇反应机理   总被引:1,自引:0,他引:1  
应用原位FT-IR详细研究了MgO上甲醇对环氧丙烷的加成反应. 结果表明在MgO催化剂上甲醇很易解离吸附形成甲氧基, 根据负碳离子机理, 吸附环氧丙烷可形成类丙烯物种. 甲氧基对类丙烯物种的加成反应遵循反-Markownikov法则, 高选择性地合成1-甲氧基-2-丙醇.  相似文献   

2.
Na2WO4—H2O2酸体系催化氧化1—甲氧基—2—丙醇的研究   总被引:5,自引:0,他引:5  
研究了Na2WO4-H2O2体系在催化氧化1-甲氧基-2-丙醇为甲氧基丙酮反应中的催化活性,发现酸助剂及添加物对甲氧基丙酮的收率有较大的影响。酸助剂中,NaHSO4对活性的促进作用最好;而H2PO4^-和HPO4^2-对体系的活性不利。极性小分子甲醇、乙腈可促进1-甲氧其-2-丙醇的氧化,提高甲氧基丙酮的收率。同时还考察了甲醇量对甲氧基丙酮收率的影响。  相似文献   

3.
2-乙烷氧基丙烯,特别是2-甲氧基丙烯,对合成脂溶性维生素 A、E 和 K_1的反应过程有极重要的作用。等研究了由丙二烯、乙炔和甲醇,在水里催化合成2-甲氧基丙烯的动力学,找到了连续进行反应的最佳条件。  相似文献   

4.
在-40~-30°下全氟环氧丙烷与氢氧化钾的甲醇水溶液作用,部分转变为α-甲氧基四氟丙酸;而与过氧化氢、氢氧化钾在甲醇水溶液中作用,部分分解为三氟乙酸.在-40~-30°,全氟丙烯与氢氧化钾的甲醇水溶液作用几乎定量地转变为1,1,2,3,3,3-六氟丙基甲基醚.  相似文献   

5.
胡艾希  陈平  袁帅  周勇 《合成化学》2002,10(4):333-334
室温下,6-甲氧基-2-丙酰基萘和1,3-二溴-5,5-二甲基海因的溴化反应在醇溶剂中,反应速度快、转化率高,生成5-溴-6-甲氧基-2-丙酰基萘的收率高(98.59%)。  相似文献   

6.
将β-环糊精的2,3位引入甲氧乙基,6位引入苄基,合成新的环糊精衍生物2,3-二-O-甲氧乙基-6-O-苄基-β-环糊精,并采用静态法涂渍5g·L~(-1)新环糊精制备石英毛细管色谱柱,考察了毛细管柱的柱性能和分离性能。结果表明:该固定相对Grob试剂、苯的二取代位置异构体二氯苯、硝基甲苯和溴甲苯以及手性化合物α-乙基-2-甲氧基苯甲醇、α-乙基-3-甲氧基苯甲醇、α-甲基-对氯苯乙腈、α-苄基-对氯苯乙腈、1-(2′,4′-二氯苯氧基)-2-丙醇和2-溴丙酸甲酯都具有良好的分离效果。  相似文献   

7.
溶剂对丙烯环氧化反应活性的影响   总被引:4,自引:0,他引:4  
研究了溶剂对钛硅分子筛催化丙烯环氧化反应的影响.研究结果表明,随着溶剂极性增加,活性中间过渡态中的过氧键越易断裂,容易把氧原子传递给丙烯,因此丙烯环氧化反应活性增加.由于TS—1催化剂孔道狭小,产生空间位阻效应,醇溶剂分子越大,活性中间过渡态的形成越困难,反应活性越低.甲醇-丙醇混合溶剂中丙酮含量小于50%时,反应活性与纯甲酵做溶剂相近;混合溶剂中丙酮含量增加到80%时,反应活性略降低;丙酮含量进一步增加,反应活性急剧下降.  相似文献   

8.
邹耀洪 《分析测试学报》2005,24(5):14-16,21
以2-氨基-2-甲基-丙醇为脂肪酸的化学修饰试剂,气相色谱一电子轰击质谱(GC-EI MS)分析葵子油脂肪酸。2-氨基-2-甲基-丙醇将脂肪酸羧基修改为含氮杂环,使在EI源中避免了链烯基中碳碳双键的移动。解析了葵子油脂肪酸2-氨基-2-甲基-丙醇化学修饰产物的EI质谱图,讨沦了烯酸中碳碳双键的定位规则,确定了葵子油脂肪酸中碳碳双键的位置。鉴定出葵子油6种脂肪酸,不饱和脂肪酸相对含量为89.41%,其中人体必需脂肪酸9,12-十八碳二烯酸含量占65.30%。本方法为不饱和脂肪酸中双键的定位提供了新的技术手段。  相似文献   

9.
CuO-NiO/SiO2催化氧化1-甲氧基-2-丙醇合成甲氧基丙酮   总被引:6,自引:0,他引:6  
 采用浸渍法制备了CuO-NiO/SiO2负载型催化剂.以空气为氧源,对CuO-NiO/SiO2催化体系催化氧化1-甲氧基-2-丙醇合成甲氧基丙酮反应的催化活性进行了考察.实验结果表明,NiO组分的负载量对催化活性影响较大;NiO和CuO两者之间有很强的协同催化效应.TPR和XRD结果表明,添加镍组分可促进铜在载体表面上分散,使氧化物还原温度降低,提高催化活性.在优化条件下,1-甲氧基-2-丙醇的转化率可达74.3%,甲氧基丙酮的收率可达63%.  相似文献   

10.
1.本文叙述从苯-乙烯酮或对硝基苯乙烯酮开始用甲氧汞化反应合成α-溴-β-甲氧基-苯丙酮或α-溴-β-甲氧基-对硝基苯丙酮。此两种溴化物均与邻苯二甲酰亚胺钾作用生成单及双邻苯二甲酰亚胺衍生物。 2.α-邻苯二甲酰亚胺-β-甲氧基-对硝基苯丙酮以异丙醇铝还原获得DL-threo-l-对硝基苯-2-邻苯二甲酰亚胺-3-甲氧基丙醇,其构型的确定系制成其醋酸酯后与已知物比较而证明。 3.β-甲氧基-对硝基苯丙酮与溴在醋酸中作用不能取得单溴化合物而获得α,β-双溴对硝基苯丙酮。后者与邻苯二甲酰亚胺钾生成双-邻苯二甲酰衍生物。此化合物以异丙醇铝还原获得1-对硝基苯-2.3-双邻苯二甲酰亚胺丙醇。  相似文献   

11.
The standard enthalpies of solution of benzene at 25°C in alcohols (methanol, 1-propanol, 1-pentanol, 1-decanol), aprotic solvents (1,4-dioxane, acetone, acetonitrile, dimethyl sulfoxide, dimethylformamide, propylene carbonate), and mixtures of methanol with these aprotic solvents were determined. Multiple regression analysis revealed the role of specific and nonspecific interactions in solvation of benzene in these solvents.  相似文献   

12.
Alcohol transformation to transportation fuel-range hydrocarbon over HZSM-5 (SiO2/Al2O3 = 30) catalyst was studied at 360 °C and 300 psig. Product distributions and catalyst life were compared between methanol, ethanol, 1-propanol and 1-butanol as a feed. The catalyst life for 1-propanol and 1-butanol was more than double compared with that for methanol and ethanol. For all the alcohols studied, the product distributions (classified to paraffin, olefin, naphthene, aromatic and naphthalene compounds) varied with time on stream (TOS). At 24 h TOS, liquid product from 1-propanol and 1-butanol transformation primarily contains higher olefin compounds. The alcohol transformation process to higher hydrocarbon involves a complex set of reaction pathways such as dehydration, oligomerization, dehydrocyclization and hydrogenation. Compared with ethylene generated from methanol and ethanol, oligomerization of propylene and butylene has a lower activation energy and can readily take place on weaker acidic sites. On the other hand, dehydrocyclization of the oligomerized products of propylene and butylene to form the cyclic compounds requires the sites with stronger acid strength. Combination of the above mentioned reasons are the primary reasons for olefin rich product generated in the later stage of the time on stream and for the extended catalyst life time for 1-propanol and 1-butanol compared with methanol and ethanol conversion over HZSM-5.  相似文献   

13.
温和条件下电催化CO2与环氧丙烷合成碳酸丙烯酯   总被引:1,自引:0,他引:1  
 在常温常压下研究了CO2的电化学活化及其与环氧丙烷反应合成碳酸丙烯酯,考察了支持电解质对碳酸丙烯酯产率的影响. 结果表明,含有Br-的支持电解质对合成碳酸丙烯酯起到明显的催化效果. 在实验研究基础上,对反应机理进行了初步推测,认为Mg2+起到路易斯酸的作用并与环氧丙烷的氧原子配位,同时Br-作为亲核试剂进攻环氧丙烷的 C-O 键使其断裂开环,形成的中间物与CO2还原产生的活化物质结合形成碳酸丙烯酯.  相似文献   

14.
A series of basic and acidic ionic liquids, 1-butyl-3-methylimidazolium hydroxide (BMIMOH), 1-acetyl-3-methylimidazolium chloride (AcMIMCl) and AcMIMCl-FeCl3, or analogues of AcMIMCl, namely 1-potassium acetate-3-methylimidazolium chloride (KAcMIMCl), 1-potassium (sodium, ammonium) acetate-3-methylimidazolium hydroxides (KAcMIMOH, NaAcMIMOH and NH4AcMIMOH), were prepared and used as catalysts for catalytic synthesis of propylene glycol ether via reaction of propylene oxide (PO) with methanol under mild reaction conditions. KAcMIMOH exhibited outstanding catalytic performance with 94.2% of conversion of PO and 99.1% of selectivity to 1-methoxy-2-propanol (MP-2) at 60°C and ambient pressure for 4 h. However, AcMIMCl-FeCl3 showed a good catalysis performance with high selectivity to 2-methoxy-1-propanol (MP-1). The tunable synthesis of MP-2 or MP-1 catalyzed by basic compound KAcMIMOH or acidic ionic liquid AcMIMCl-FeCl3 was realized.  相似文献   

15.
含氟聚合物杂化电解质膜的结构分析   总被引:1,自引:0,他引:1  
聚偏氟乙烯;共聚物;微孔膜;离子电导率;含氟聚合物杂化电解质膜的结构分析  相似文献   

16.
甲醇和碳酸丙烯酯合成碳酸二甲酯的研究   总被引:7,自引:0,他引:7  
采用浸渍法以ZrO2为载体,以碱金属氢氧化物和碳酸盐为前驱体制备了不同的固体碱催化剂,在温和反应条件下考察了催化剂的酯交换扳应性能,并通过BET、XRD和CO2-TPD等方法对催化剂进行了表征,结果表明:Na2CO3负载到不同载体上,其催化性能明显不同,Na2CO3/ZrO2催化剂获得了较高的酯交换活性。载体的比表面和孔结构与催化剂的反应活性无一定的依存关系。而催化剂表面的酸碱性是影响酯交换活性的重要因素。  相似文献   

17.
刘宁  刘水林  伍素云  唐新德  吴智  李爱阳 《应用化学》2019,36(11):1294-1300
为了缩短有序介孔氧化硅(SBA-15)基固体碱催化剂的工艺流程,制备长程有序介孔固体碱,本文以十六烷基三甲基溴化胺(CTAB)-三嵌段表面活性剂P123为模板剂,以KF为改性剂,两步法合成有序介孔KF/Al-Ce-SBA-15(KF/ACS)固体碱催化剂,采用小角X射线衍射(小角XRD)、N2吸附-脱附曲线、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、CO2程序升温脱附(CO2-TPD)等手段,对催化剂的结构与性能进行表征,并研究了其在合成丙二醇甲醚(PM)中的催化性能。 当n(Al)/n(Ce)=0.12,KF的质量分数为10%时,KF/ACS催化剂不仅能够保持长程有序介孔结构,并且显示出强碱性能。 在催化甲醇与环氧丙烷(PO)合成PM的反应中,PM的收率达到92.0%,1-甲氧基-2-丙醇(PPM)选择性达到96.1%以上,并能有效抑制二丙二醇甲醚等副产物。  相似文献   

18.
Simple mixing of H3Co(CN)6 and ZnCl2 in methanol resulted in precipitates of [ZnCl]+2[HCo(CN)6]2?, constituting a new type of double metal cyanide (DMC) catalyst exhibiting a high performance in carbon dioxide (CO2)/propylene oxide (PO) copolymerization. High‐molecular‐weight poly(propylene carbonate‐co‐propylene oxide)s [poly(PC‐co‐PO)s] (Mn~40,000) were consistently obtained with high carbonate fractions (~60 mol %) and a high selectivity (>95%) with the new type of DMC catalyst. Conventional preparation of the DMC catalyst using K3Co(CN)6 and ZnCl2 required removing KCl through thorough washing and resulted in lower carbonate fractions (10–40 mol %), which depended on the washing conditions. Feeding hydrophobic diols such as 1,10‐decanediol as chain transfer agent preserved the high carbonate fraction (~60%) and enabled precise control of the molecular weight, including preparation of a low‐molecular‐weight poly(PC‐co‐PO)‐diol (Mn ~2000), which was a flowing viscous liquid with a low Tg (?30 °C) suitable for polyurethane applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4811–4818  相似文献   

19.
《Fluid Phase Equilibria》2002,201(1):187-201
Isobaric vapour–liquid equilibria have been experimentally determined for the binary systems methanol+dimethyl carbonate, ethanol+dimethyl carbonate, dimethyl carbonate+1-propanol, dimethyl carbonate+1-butanol and dimethyl carbonate+1-pentanol at 101.3 kPa. The activity coefficients were calculated to be thermodynamically consistent and were correlated with the Wilson and UNIQUAC equations. Interaction parameters related to the carbonate group (OCOO) and alcohols, in ASOG and UNIFAC methods, have been determined using our experimental VLE data. The experimental results, as well as those by other authors, agree with the calculated VLE using the new ASOG and UNIFAC parameters.  相似文献   

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