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分别考察了常规条件下和微波合成条件下,碘催化法合成7-(2-甲基-3-丁炔-2-氧基)-香豆素的研究.实验结果表明,微波合成法不仅大大缩短了反应时间,还节省了昂贵原料3-氯-3-甲基-1-丁炔的用量,是合成该产物较优的合成方法.此外,还对比考察了Mitsunobu成醚法与碘催化法合成目标产物,并对二者的反应历程进行了探讨,对DCC法合成进行了尝试. 相似文献
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1 ,4-二氯 - 2 -丁炔是合成链状脂肪烃类化合物的中间体。将 2 -丁炔 - 1 ,4-二醇和 PCl3 混合于CH2 Cl2 中 ,在吡啶的存在下 ,以六甲基磷酰胺 ( HMPA)为催化剂 ,反应物回流 1 2 h,1 ,4-二氯 - 2 -丁炔的得率可达 72 %。合成物经 IR、1H NMR及元素分析证实。 相似文献
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以7-羟基香豆素和3-氯-3-甲基-1-丁炔为原料,分别采用不同的微波合成条件,经两步合成2,2-二甲基-1,5-二氧杂菲-6-酮。实验结果表明,与传统合成方法相比,微波合成不仅大大减少了反应的时间,还降低了原料的消耗,是合成Seselin的较优方法。 相似文献
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以廉价的2-甲基-3-丁炔-2-醇为原料,经迈耶-舒斯特重排反应得到3-甲基-2-丁烯醛,再经空气氧化制得标题化合物。对重排反应条件和氧化反应条件等工艺条件进行了详细研究。结果表明,以液体石蜡为溶剂,115~125℃催化重排反应3 h,处理后可得含量为98%的3-甲基-2-丁烯醛,收率85%以上;3-甲基-2-丁烯醛以微量氯化亚铜为催化剂,35℃以下通空气氧化,得到含量为97.5%的3-甲基-2-丁烯酸,收率90%以上。该方法原料廉价易得,工艺路线短,收率较高,对环境友好,是一种有前途的方法。 相似文献
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以2-丁炔-1,4-二(对甲苯磺酸酯)为起始原料,在AlCl3催化下和苯发生傅-克烷基化反应,合成2-丁炔-1,4-二苯。考察了AlCl3和磺酸酯的物质的量比、溶剂种类和用量、反应时间、反应温度对产物收率的影响,确定适宜的反应条件如下:n(AlCl3)∶n(磺酸酯)∶n(苯)为2.6∶1∶2.8、反应时间为2h、反应温度为40℃,在此条件下,2-丁炔-1,4-二苯收率为60.1%。产物经元素分析、IR和1HNMR确证。 相似文献
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以糠醛为初始原料经过制取2-甲基呋喃、2-甲基-2,5-二甲氧基-5-二氢呋喃、2-甲基-3-乙酰硫基呋喃等步骤,合成了2-甲基-3-呋喃硫醇。考察了合成工艺条件对产物收率的影响,确定了最佳合成工艺条件:n(2-甲基-3-乙酰硫基呋喃)∶n(NaOH)∶n(NaH2PO4)=1.00∶0.51∶0.99,乙酸加入量3 mL,反应温度95°C,反应时间20 min,在5.90 kPa下收集57~59.5°C的馏分,在此条件下,收率可达83%。 相似文献
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The isomerization of 2,3-dimethylbut-1-ene and the decomposition of 2-methyl-3-butyn-2-ol were carried out over a number of solid base catalysts. Rubidium amide supported on alumina was the most active for the isomerization, which proceeds almost to the equilibrium in 10 min at 201 K. The isomerization is a very useful test reaction for determining the relative activities of very strong solid bases. However, weak solid bases such as K+-exchanged Y zeolite are totally inactive for the isomerization. The decomposition of 2-methyl-3-butyn-2-ol is a suitable reaction to discriminate acidic and basic catalysts. It can be also used for estimating the basic property of weak bases such as lithium hydroxide supported on alumina. However, caution is necessary for strongly basic catalysts because of strong adsorption of the products, acetylene and acetone. 相似文献
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Sonogashina偶联法合成芳基末端炔的工艺改进 总被引:1,自引:0,他引:1
以对二溴苯(Ⅰa)、1,3,5-三溴苯(Ⅰb)和2-甲基-3-丁炔-2-醇(Ⅱ)为原料,在PdC l2、PPh3和CuI的催化作用下进行Sonogash ina偶联反应,偶联产物在KOH作用下发生消去反应,分别得到对溴苯乙炔(Ⅳa)、对二乙炔基苯(Ⅳa′)、1,3,5-三乙炔基苯(Ⅳb)。研究发现,在合成中间体1,4-二(3-羟基-3-甲基-1-丁炔)苯时,选择n(Ⅰa)∶n(Ⅱ)=1∶3较为适合;共催化剂n(CuI)∶n(Ⅱ)≈0.01时产率较高;水对偶联反应无影响。粗产物经硫酸铜溶液萃取、硅胶过滤、重结晶、真空升华进行分离提纯得到纯产品。3种产物的收率分别为75%、72%、70%。产物用IR、GC-MS、1HNMR进行了确证。 相似文献
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Micaela Crespo-Quesada Martin Grasemann Natalia Semagina Albert Renken Lioubov Kiwi-Minsker 《Catalysis Today》2009,147(3-4):247
The solvent-free selective hydrogenation of 2-methyl-3-butyn-2-ol (MBY) to 2-methyl-3-buten-2-ol (MBE) was studied over a Pd/ZnO structured catalyst and compared to its behavior in water-assisted conditions. The catalytic behavior was correlated with the surface properties of the catalysts which were characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The catalyst showed high selectivity and stability with the performance being superior to that of the industrial Lindlar catalyst (50%). The addition of a sulphur-containing modifier in the reaction mixture was found to affect the activity and to hinder the over-hydrogenation reaction. The MBE yield of 97% was attained at MBY conversion >99%. The reuse of the catalyst showed that it deactivated by a 38% and that its selectivity slightly increased (0.5%) over 10 runs. The reaction kinetics was modeled using a Langmuir–Hinshelwood mechanism considering competitive adsorption for the organic species and dissociative adsorption for hydrogen. The kinetic experiments were planned and the results analyzed following a design of experiments (DOE) methodology. This approach led not only to a robust model that predicts the reaction rate in a wide range of reaction conditions but also to the determination of its kinetic parameters. 相似文献
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Richard J. Anderson Henry R. Chinn Karen Gill Clive A. Henrick 《Journal of chemical ecology》1979,5(6):919-927
The two components of the sex pheromone of the San Jose scale,Quadraspidiotus perniciosus (Comstock) were synthesized. The first component, 7-methyl-3-methylene-7-octen-1-yl propanoate, was obtained by the addition of a 4-methyl-4-penten-1-yl copper complex to 3-butyn-1-yl propanoate (or 3-butyn-1-yl trimethylsilyl ether). Reaction of the same copper complex with propyne followed by treatment with carbon dioxide gave a key intermediate in the stereoselective synthesis of (Z)-3,7-dimethyl-2,7-octadien-1-yl propanoate, the second component of the pheromone.Quadraspidiotus perniciosus (Comstock) (Homoptera: Diaspididae).Contribution No. 73 from the Research Laboratory of Zoecon Corporation. 相似文献
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2-甲基-3-丁烯-2-醇合成3-甲基-2-丁烯-1-醇 总被引:1,自引:0,他引:1
[目的]2-甲基-3-丁烯-2-醇是异戊二烯间接皂化法生产3-甲基-2-丁烯-1-醇过程中产生的副产物,废物回收再利用是节能减排的有效措施.[方法]2-甲基-3-丁烯-2-醇经氯化、酯化和皂化得到3-甲基-2-丁烯-1-醇.[结果]结果表明:在优化条件下,氯化反应的产率可达87.25%,酯化和皂化反应的产率可达84.53%.[结论]该方法是2-甲基-3-丁烯-2-醇再利用的有效方法. 相似文献
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