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1.
室温离子液体中催化合成肉桂酸苄酯   总被引:14,自引:0,他引:14  
研究离子液体中肉桂酸钾和氯化苄经缩合合成肉桂酸苄酯的新方法,并对多种离子液体的作用性能进行了考察.研究结果表明,离子液体中BMImBF4的催化性能最佳,但是肉桂酸苄酯的收率仍不高,只有当相转移催化剂四丁基氯化铵存在时,肉桂酸钾与溶于离子液体中的氯化苄在温和的反应条件下才可高效率地得到肉桂酸苄酯,收率可达96.5%.产物分离简单,离子液体和相转移催化剂形成的双催化体系可以稳定地循环使用5次以上.  相似文献   

2.
Girdhar Joshi 《合成通讯》2013,43(5):720-728
The synthesis of benzyl alkyl ethers from benzyl bromides and alcohols using FeSO4 as a recoverable and reusable mediator has been described without use of base and cosolvent under mild conditions.  相似文献   

3.
室温离子液体中乙酸钠和氯苄催化合成乙酸苄酯   总被引:9,自引:0,他引:9  
顾彦龙  杨宏洲  邓友全 《化学学报》2002,60(9):1571-1574
在多种1,3-二烷基咪唑和烷基吡啶室温离子液体中考察了较温和条件下乙酸 钠和氯化苄作用合成乙酸苄酯反应。在反应温度下(60 ℃),熔融的三水合乙酸 钠与离子液体相混溶,氯苄同乙酸钠作用得到乙苄酯,它与四氟硼酸1-乙基-3-甲 基咪唑离子液体不溶而分层。反应结束后产物乙酸苄酯可直接倾析得到,乙酸苄酯 产率达到90%,纯度超过99%。此离子液体催化体系简化了产物分离,离子液体可以 重复使用。  相似文献   

4.
A novel type of palladium-catalyzed cascade cyclization-coupling reaction has been found. Reaction of N, N-diallylbenzoylamide 1 with benzyl halides 2 afforded the corresponding dihydropyrroles 3 in moderate to excellent yields.  相似文献   

5.
Ramesh Naik 《合成通讯》2013,43(21):2823-2826
Primary benzyl amines, upon treatment with aq. NaNO2 and appropriate organic acids at 0–5°C, give their respective benzyl esters.  相似文献   

6.
硫酸氢钠催化合成羧酸苄酯   总被引:10,自引:0,他引:10  
讨论了一水硫酸氢钠催化合成乙酸苄酯的条件。羧酸、苄醇和硫酸氢钠的质量比为 3∶2∶0 .1 45 ,以环己烷为溶剂 ,进行回流分水 ,合成了甲酸苄酯、乙酸苄酯、丙酸苄酯和丁酸苄酯 ,其收率为 68.5 %~ 84.1 %  相似文献   

7.
Carbonylation of benzyl halides to phenylacetic acid was studied in a two-phase system with iron pentacarbonyl as the catalyst precursor. The solutions consisted of a benzyl halide and iron pentacarbonyl in benzene and tetrabutylammonium hydrogen sulfate in aqueous sodium hydroxide. Stirring under carbon monoxide readily produced phenylacetic salts in aqueous phase which were then acidified and extracted with ether. The yields of phenylacetic acid from benzyl iodide and from benzyl bromide were similar at a evel of about 50percnt;, that of the latter being higher by 1%. The yield from benzyl chloride was far less, at a level of only 21%. The rate as studied with gas chromatography was found to decrease in the order benzyl iodide>benzyl bromide>benzyl chloride.  相似文献   

8.
合成了一系列过渡金属Zn取代的Keggin型磷钨杂多酸的季铵盐,采用傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)等方法表征了杂多化合物的结构.并将其用于苯甲醇无溶剂氧化合成苯甲醛的反应,考察了催化剂种类、反应条件对苯甲醇氧化的影响.实验结果表明,在无任何溶剂的情况下,Zn取代的Keggin型磷钨四丁基铵盐具有最佳的催化活性,反应时间仅为30 min,苯甲醇的转化率可以达到95.6%,苯甲醛的选择性达到了96.4%.在对杂多酸季铵盐结构的研究基础上,对可能的反应机理进行了初步探讨.  相似文献   

9.
可膨胀石墨催化合成乙酸苄酯   总被引:4,自引:0,他引:4  
可膨胀石墨作为一种重要的非金属材料已广泛应用于各工业领域 ,将其作为有机质反应催化剂的研究尚不多见[1~ 3] 。工业上 ,乙酸苄酯常是以浓H2 SO4、对甲苯磺酸等质子酸作催化剂由乙酸和苄醇制得[4] ,但此法腐蚀设备 ,污染环境 ,且副反应多。近年来 ,为了寻找对设备腐蚀性小的酯化反应催化剂进行了一些研究 ,如曾报道的酯化反应催化剂有 :四氯化锡复合物[5] 、复合固体超强酸[6] 、稀土硫酸盐[7]等。本文报道可膨胀石墨催化乙酸苄酯的合成 ,与其它催化剂相比 ,具有催化活性高 ,反应温度低 ,反应时间短 ,收率高 ,易分离及再生处理简单等…  相似文献   

10.
The kinetics is studied for the phase transfer catalytic preparation of benzyl benzoate from sodium benzoate and benzyl chloride with tetrabutylaramonium iodide as catalyst in a well stirred batch reactor. Benzyl chloride is dissolved in toluene as the organic phase and sodium benzoate is dissolved in water as the aqueous phase. The kinetics of the overall reaction is described by a first-order model based on the concentration of benzyl chloride in the organic phase at the later time of the batch reaction. The rate constant increases with an increase of the catalyst concentration while decreases slightly with an increase of the concentration of sodium benzoate under the experimental condition.  相似文献   

11.
纳米孔炭负载 MnOx 催化剂上苯甲醇氧化反应性能   总被引:1,自引:0,他引:1  
 以纳米孔炭 (NC) 为载体, 采用浸渍法制备了一系列 MnOx/NC 催化剂, 并用于以空气为氧源的苯甲醇液相氧化反应. 通过 X 射线衍射、X 射线光电子能谱、N2 吸附-脱附和 H2-程序升温还原等手段对催化剂进行了表征, 考察了催化剂中 Mn 负载量和焙烧温度, 以及反应条件等对反应性能的影响. 结果表明, 10%MnOx/NC 催化剂的活性较高, 反应 4 h 后苯甲醇转化率可达 80.4%; 明显高于活性炭负载的 MnOx 催化剂. 这主要归因于其表面存在大量高分散、且易于还原的 Mn 物种.  相似文献   

12.
溴化苄的合成工艺研究   总被引:1,自引:0,他引:1  
以二苄醚和氢溴酸为原料,SO42-/TiO2为催化剂,环已烷为带水剂,合成了溴化苄。实验分别考察了反应物摩尔比、反应时间、反应温度、带水剂的用量,催化剂的使用量等因素对溴化苄收率的影响,得出了用此方法合成溴化苄的最佳反应条件:氢溴酸与二苄醚的摩尔比为3:1,反应时间为8 h,环已烷为8 mL,SO42-/TiO2催化剂的用量为0.5 g,溴化苄的收率达80.2%。  相似文献   

13.
盛学斌  马红  李德财  何静  徐杰 《催化学报》2010,31(7):822-826
 以亚硝酸异戊酯为催化剂, 通过固体磺酸的促进作用原位产生亚硝酰正离子, 实现了催化氧气氧化苯甲醇制备苯甲醛. 300 oC 处理的 Amberlyst 15 表现出较高的促进效果, 在 0.5 MPa O2, 80 oC 反应 2 h, 苯甲醇转化率和苯甲醛选择性可分别达到 90% 和 97%. 通过红外、热分析及酸碱滴定研究了不同方法制得的固体酸的差别及其对反应促进效果的影响, 并利用紫外-可见光谱和衍生化方法检测了亚硝酰正离子.  相似文献   

14.
Catalytic oxidation reactions often suffer from drawbacks such as low yields and poor selectivity. Particularly, selective oxidation of alcohols becomes more difficult when a compound contains more than one oxidizable functional group. In order to deliver a methodology that addresses these issues, herein we report an efficient, aerobic, chemoselective and simplified approach to oxidize a broad range of benzyl and propargyl alcohols containing diverse functional groups to their corresponding aldehydes and ketones in excellent yields under mild reaction conditions. Optimal yields were obtained at room temperature using 1 mmol substrate, 10 mol % copper(I) iodide, 10 mol % 4-dimethylaminopyridine (DMAP), and 1 mol % 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) in acetonitrile, under an oxygen balloon. The catalytic system can be applied even when sensitive and oxidizable groups such as alkynes, amines, and phenols are present; starting materials and products containing such groups were found to be stable under the developed conditions.  相似文献   

15.
Green oxidation of benzyl halides to the corresponding aldehydes or ketones was achieved in aqueous media using trimethylamine N-oxide generated in situ from trimethylamine and H2O2. The yield of the reaction was excellent and the workup was simple.  相似文献   

16.
硫酸高铈催化合成丙酸苄酯   总被引:8,自引:0,他引:8  
吴长增  宋晓平 《合成化学》2002,10(4):351-352
以结晶硫酸高铈为催化剂对丙酸苄酯的合成进行了研究,考察了反应时间、催化剂用量、醇酸摩尔比和带水剂等因素对反应的影响,结果表明,在最佳反应条件下,酯化率在85%以上。  相似文献   

17.
对羟基苯甲酸苄酯的合成   总被引:18,自引:0,他引:18  
制备;相转移催化;对羟基苯甲酸苄酯的合成  相似文献   

18.
Benzyl phenyl ether is prepared in a well-stirred batch reactor from phenol and benzyl chloride using tetrabutylammonium iodide as phase transfer catalyst. Phenol with sodium hydroxide is dissolved in water as the aqueous phase, and benzyl chloride is dissolved in toluene as the organic phase. Tetrabutylammonium iodide gives high reaction rate without the formation of micelles during the reaction. The reaction mechanism is verified by infrared spectrum study and other experimental observations. The kinetics of the reaction of benzyl chloride is modelled as a first-order chemical reaction. The cocatalytic effect of the iodide ion, and salting out effect on the overall reaction rate are discussed in detail using experimental data.  相似文献   

19.
功能化离子液体室温催化合成乙酸苄酯   总被引:5,自引:1,他引:4  
制备了N-甲基-N′-磺酸烷基-咪唑阴离子型功能化室温离子液体,研究了功能化室温离子液体(TSILs)于室温下催化乙酸和苯甲醇反应合成乙酸苄酯的新方法,考察了多种TSILs的催化性能。结果表明,所合成的TSILs具有很高的催化活性,乙酸和苯甲醇的摩尔比为1:1.3,在室温下反应2.5 h,乙酸苄酯的产率可达92%,选择性超过99%。由于生成的乙酸苄酯不溶于催化体系,反应产物与催化体系分层,通过简单的倾析便可实现产物分离,简化了分离过程。离子液体可以循环使用,而其催化活性没有明显降低。  相似文献   

20.
李金恒  刘文杰  梁云  谢叶香 《有机化学》2005,25(9):1045-1048
硫酸亚铈作为一种便宜的和有效的催化剂催化芳香化合物与苄基醇、烯丙醇类化合物和苄基氯的傅-克烷基化反应. 在1~10 mol%的硫酸亚铈存在下, 芳香化合物分别与苄基醇、烯丙醇类化合物和苄基氯能够顺利有效地进行傅-克烷基化反应. 此外, 催化剂能回收, 再次使用三次也没有明显地失去催化活性.  相似文献   

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