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121.
(+)-2-甲基-4-戊烯酸的合成   总被引:3,自引:0,他引:3  
丙二酸二乙酯与碘甲烷反应生成二乙基甲基丙二酸酯(1). 由(1)进行皂化和脱羧反应制备2-甲基-4-戊烯酸(4).用一种新的拆分剂葡辛胺拆分(4)得到(+)-2-甲基-4-戊烯酸.  相似文献   
122.
四氯化锡催化合成己二酸二丁酯   总被引:9,自引:0,他引:9  
应用五水四氯化锡催化己二酸和正丁酯的酯化反应,合成了己二酸二丁酯。研究结果表明,五水四氯化锡具有较高的催化活性。考察了己二酸/正丁醇摩尔比和催化剂用量对酯产率的影响,在适宜反应条件[n(己二酸):n(正丁醇):n(四氯化锡)=1:8:0.114,回流反应60min]下,己二酸二丁酯的产率为96.9%。  相似文献   
123.
A facile route for the synthesis of dimethyl adipate (DAP) from cyclopentanone and dimethyl carbonate (DMC) in the presence of solid base catalysts has been developed.It was found that the intermediate carbomethoxycyclopentanone (CMCP) was produced from cyclopentanone with DMC in the first step,and then CMCP was further converted to DAP by reacting with a methoxide group.The role of the basic catalysts can be mainly ascribed to the activation of cyclopentanone via the abstraction of a proton in the α-position by base sites,and solid bases with moderate strength,such as MgO,favor the formation of DAP.  相似文献   
124.
贺红举 《化学研究》2013,(6):622-624
采用毛细管气相色谱法(GC)测定了二乙基二硫的含量.结果表明,二乙基二硫含量在0.010.4g/L范围内具有良好的线性关系,平均回收率为99.91%;该方法简便、准确、重复性好,可方便地用于二乙基二硫含量的测定.  相似文献   
125.
以3,4-二氯苯胺和乙氧基亚甲基丙二酸二乙酯为起始原料,经缩合、Gould-Jacobs环合、水解、脱羧及氯化反应合成了含4-氨基喹啉结构抗肿瘤化合物的关键中间体——4,6,7-三氯喹啉,总收率54.21%,其结构经1H NMR,IR和ESI-MS确证。  相似文献   
126.
The polymorphic crystalline structure and melting behavior of biodegradable poly(butylene adipate) (PBA) samples melt‐crystallized at different crystallization temperatures were studied by differential scanning calorimetry (DSC) and fourier transform infrared (FTIR) spectroscopy. The crystalline structure and melting behavior of PBA were found to be greatly dependent on the crystallization temperature. By comparison of the FTIR spectra and the corresponding second derivatives between the α‐ and β‐crystal of PBA, the spectral differences were identified for the IR bands appeared at 1485, 1271, 1183, and 930 cm?1 and the possible reasons were presented. Especially, the 930 cm?1 band was found to be a characteristic band for the β‐crystal. Combining the DSC data with the analysis of normalized intensity changes of several main IR bands during the melting process, the melting behaviors of the α‐ and β‐crystal were clarified in detail. It is demonstrated by the in situ IR measurement that the β‐crystalline phase would transform into the α‐crystalline phase during the melting process, and the solid–solid phase transition from the β‐ to α‐crystal was well elucidated by comparing the intensity changes of the 1170 and 930 cm?1 bands. The dependence of the β‐ to α‐crystal phase transition on the heating rate was revealed by monitoring the intensity ratio of the 909 and 930 cm?1 band. It was suggested that at the heating rate of 0.5 or 1 °C/min, the percent amount of the transformed α‐crystal from the β‐crystal was much higher than that at the higher heating rate. The β‐crystal transforms into the α‐crystal incompletely at the higher heating rate because of the less time available for the phase transition. In addition, the β‐ to α‐crystal phase transition was further confirmed by the IR band shifts during the melting process. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1997–2007, 2009  相似文献   
127.
The synthesis of diethyl oxalate from ethyl nitrite and carbon monoxide in gaseous phase has been studied at atmospheric pressure. Kinetics of coupling - regeneration reaction has been determined and the optimization of the reaction has been simulated. The influences of gas impurities has also been studied. Scale-up circulating shows that the concentrate and selectivity were stable in the product and the process is suitable for industrial production. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
128.
王艳  张树东  朱湘君  孔祥和 《物理学报》2007,56(8):4491-4496
应用激光多光子电离质谱与超声脉冲分子束技术研究了乙醚团簇,实验中观测到乙醚的碎片离子以及强度较小的(E)H+,(E)2和(E)2H+(E代表CH3CH2OCH2CH3),没有发现更大尺寸的团簇离子.结合从头计算理论,在B3LYP/6-311++G(d,p 关键词: 乙醚团簇 偶极-偶极相互作用 从头计算  相似文献   
129.
Visible-light transparent high-quality substrate-supported poly(2,3-benzofuran) (PBF) film has been successfully electrosynthesized by direct anodic oxidation of 2,3-benzofuran on stainless steel sheet in boron trifluoride diethyl etherate (BFEE) containing 10% poly(ethylene glycol) (PEG) with molar mass of 400 (by volume). The oxidation potential of 2,3-benzofuran in this medium was measured to be only 1.0 V vs. SCE, which is lower than that determined in acetonitrile + 0.1 M Bu4NBF4 (1.2 V vs. SCE). The PBF films obtained in this media showed good electrochemical behaviors and good thermal stability with conductivity of 10−2 S cm−1, and the doping level of as-prepared PBF films was determined to be only 8.9%. The structure and morphology of the polymer were investigated by UV-vis, infrared spectroscopy and scanning electron microscopy (SEM), respectively. To the best of our knowledge, this is the first case for the syntheses of PBF films.  相似文献   
130.
从磷硅试剂合成烃基膦酯类化合物   总被引:1,自引:1,他引:0  
本文报导三甲基硅氧基亚磷酸酯(一种活性较高的磷硅试剂)与醛酮反应而获得十四个二乙基三甲硅氧基烃基膦酸酯。产物结构经IR,~1HNMR,~(31)PNMR,MS测试和元素分析表征;对反应机理作了初步讨论。  相似文献   
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