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研究了微波协同大孔树脂催化合成肉桂酸正丙酯和异丁酯的扩大实验。结果表明,合成肉桂酸正丙酯的优化工艺条件为:肉桂酸7.4g,正丙醇19mL,CAT-600大孔树脂6.8g,微波功率400W,反应时间为25min,酯化率92.89%;合成肉桂酸异丁酯的优化工艺条件为:肉桂酸10g,异丁醇45mL,NKC-9大孔树脂14g,微波功率600W,反应时间为35min,酯化率90.18%。 相似文献
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研究了微波协同大孔树脂催化合成肉桂酸正戊酯和异戊酯的扩大实验。结果显示,合成肉桂酸正戊酯的优化工艺条件为:肉桂酸7.4g,正戊醇17mL,CAT-600大孔树脂6.4g,微波功率400W,反应时间为8min时,酯化率97.23%;合成肉桂酸异戊酯的优化工艺条件为:肉桂酸7.4g,异戊醇19mL,CAT-600大孔树脂8.1g,微波功率700W,反应时间为8min时,酯化率97.01%。 相似文献
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1.合成了三种异烟酰肼的衍生物,即 sym-氯乙酰基-异烟醯基肼、sym-三氯乙酰基-异烟酰基肼及 sym-一氯乙酰基-异烟酰肼盐酸(?)菜碱。这三种衍生物对 B.sme-gmatis 的抗菌作用分别为1∶16,000;1∶8,000;1∶8,000。2.制备了八种2,6-二氨基异烟酸酯,即甲酯、乙酯、正丙酯、异丙酯、正丁酯、异丁酯、正戊酯、异戊酯。其中甲酯为已知物,馀为新化合物。其抗 B.smegmatis 的作用均为1∶2000。3.2,6-二氨基-异烟酰肼的抗 B.smegmatis为1∶2000;2,6-二氨基-异烟酰胺及2,6-二氨基-异烟酸均无抗 B.smegmatis 作用。 相似文献
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大孔阳树脂催化合成苯乙酸酯 总被引:2,自引:0,他引:2
利用D72,D61大孔阳离子交换树脂为催化剂,催化合成苯乙酸异戊酯、苯乙酸丁酯、苯乙酸苄酸、苯乙酸苯乙酯、苯乙酸茴香酯。对影响反应的诸因素进行了讨论,酯收率为90%左右。 相似文献
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TiSiW12O40/TiO2催化合成苯甲酸酯 总被引:53,自引:1,他引:52
首次报道了以固载杂多酸盐TiSiW12O40/TiO2为催化剂,对以丙醇、丁醇、正戊醇、异戊醇和苯甲酸为原料,合成相应苯甲酸酸的反应条件进行了研究。实验表明,TiSiW12O40/TiO2是合成苯甲酸酯的良好催化剂,最佳反应条件为:醇酸摩尔比为4:1,催化剂用量为反应物料总质量的1.5%,反应时间为2.5h。在此条件下,苯甲酸丙酯及苯甲酸正丁酯的产率分别为70.5%及75.6%,苯甲酸戊酯和苯甲酸异戊酯的产率分别达96.7%和83.3%。 相似文献
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磺酸型阳离子交换树脂催化合成肉桂酸甲酯 总被引:11,自引:0,他引:11
以磺酸型阳离子交换树脂为催化剂,由肉桂酸和甲醇合成了肉桂酸甲酯。考察了反应条件对酯化反应的影响和树脂的催化稳定性。结果表明,肉桂酸的转化率可达95.5%,且催化剂的性能稳定。 相似文献
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合成了两种含有联苯刚性基元的甲基丙烯酸酯单体M1和M2,其中M1为含有可光交联的肉桂酸酯端基的单体.通过溶液自由基聚合,得到一系列含不同比例M1和M2单体单元的聚丙烯酸酯类侧链液晶共聚物.采用1H-NMR、FT-IR等方法对单体和聚合物的结构进行了详细表征.用示差扫描量热法、偏光显微镜以及广角和小角X-射线衍射对单体和聚合物的液晶性进行了研究.结果表明,末端为肉桂酸酯基团的单体M1无液晶性,其均聚物P1有微弱的液晶性,而端基为正丁基的单体M2及其均聚物P9则表现出近晶相液晶行为.共聚物P2~P5均为向列型液晶,P6~P9则为近晶型液晶.随在聚合物中M2单体含量的增加,共聚物的玻璃化转变温度、熔点及清亮点温度均呈现增加趋势. 相似文献
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Partial modification of the nonionic polymer poly(N‐2‐hydroxy‐propylmethacrylamide) by cinnamate produces stimuli‐responsive copolymers. The hydrophobic character of the cinnamate chromophore induces not only a lower critical solution temperature (LCST) in water, but renders additionally the polymers photoresponsive. For moderate cinnamate contents of 9 mol‐%, the photoisomerization of the trans‐cinnamate to cis‐cinnamate groups allows to switch the LCST by irradiation, whereas for higher cinnamate contents of 21 mol‐%, irradiation leads to intra‐ and intermolecular photocrosslinking. 相似文献
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Wijtmans M Rosenthal SJ Zwanenburg B Porter NA 《Journal of the American Chemical Society》2006,128(35):11720-11726
The photochemical properties of organic ligands on the surface of nanocrystalline CdSe particles were examined. A number of thiols carrying a substituted cinnamate tail was synthesized. In solution, these cinnamate compounds undergo light-induced (374 nm) E-Z isomerization, followed by a nonphotolytic lactonization to give highly fluorescent coumarin. The cinnamate-thiols were successfully exchanged onto the CdSe nanocrystal, and the photochemical behavior of these conjugates was studied. Upon aerobic photolysis at 374 nm, the surface cinnamates released coumarin accompanied by rapid nanocrystal degradation. This degradation was not observed under similar anaerobic conditions or when the organic ligands did not contain the cinnamate group. Surprisingly, very similar results were obtained upon irradiation at visible wavelengths at which the cinnamate has no absorption. With the aid of UV-visible absorption spectroscopy, fluorescence spectroscopy, and electrochemistry, a unified theory for both the increased photoinstability of the nanocrystal as well as the coumarin release was proposed. It involves cinnamate radical anions on the CdSe surface, formed upon electron transfer from the excited nanocrystal to the surface cinnamate, undergoing E-Z isomerization. Practically, this results in the remarkable ability to release coumarin from nanocrystal ligands simply by exciting the nanocrystal with visible light. This new photorelease protocol not only aids in the understanding of fundamental nanocrystal-ligand interactions but may also offer new opportunities in the areas of drug delivery and imaging. 相似文献
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B. Ravindran G. Madhurambal M. Mariappan K. Ramamurthi S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2011,104(3):909-914
Single crystals of mercury cinnamate were grown by slow evaporation of methanol solution at room temperature. The effect of
mercury on the electronic structure of cinnamic acid was studied. The grown mercury cinnamate single crystals were characterized
by UV, FTIR and TG-DTA. TG curve of mercury cinnamate exhibits higher thermal stability compared with cinnamic acid which
was also confirmed by DTA curve. The spectroscopic studies give evidences of the distribution of the electronic charge in
molecule, the delocalisation of π electrons and the reactivity of metal complexes. The Second harmonic generation efficiency
is more pronounced in the presence of mercury dopant in the growth medium. 相似文献
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Sanae Abrakhi Sébastien Péralta Sophie Cantin Odile Fichet Dominique Teyssié 《Colloid and polymer science》2012,290(5):423-434
The photochemical behavior of photosensitive materials obtained by spin-coating or network synthesis of a cellulosic polymer
bearing photo-cross-linkable cinnamate groups was investigated. First, cinnamate groups were grafted on a cellulose acetate
butyrate polymer, with different grafting densities. The photochemical properties of the polymers were studied in solution
by UV–visible and 1H NMR spectroscopy. Then spin-coated films and networks were prepared and characterized as a function of the number of cinnamate
groups per cellulosic unit. The water-wetting properties of both surfaces were studied by dynamic contact angle measurements,
before and after photoirradiation, and subsequent heating. The surfaces obtained by the two methods have significantly different
behaviors that can be assigned to the distinct photochemical pathways of the cinnamate groups upon irradiation depending on
the sample preparation. Indeed, dimerization reaction is evidenced as the main process in the spin-coated films while the
expected isomerization is predominant at the surface of the polymer networks. 相似文献
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肉桂酸环己酯的合成研究 总被引:4,自引:0,他引:4
肉桂酸环己酯为具有令人愉快的果香香气的无色粘稠液体 ,不溶于水 ,易溶于乙醇 ,常用于食用香精和日化香精的配料中 ,是典型的香料和食品添加剂[1,2 ] 。据报道 ,目前合成肉桂酸环己酯的方法有二 ,一是传统的硫酸催化酯化法 ,二是用路易斯酸FeCl3·6H2 O做催化剂来合成肉桂酸环己酯 ,两种方法虽有各自的优点 ,但它们的收率均不高 ,分别为 78.4%、73 .4% [3] 。近年来人们用相转移催化技术合成了许多酯类[4 ,5] ,受其启发 ,我们在催化剂浓硫酸中加入聚乙二醇 40 0作为混合催化剂来合成肉桂酸环己酯 ,获得了满意的结果 ,反应收率达 84.8… 相似文献
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Michael M. Coleman Yin Hu Maria Sobkowiak Paul C. Painter 《Macromolecular Symposia》1999,141(1):197-215
Vibrational spectroscopic studies of a series of ethylene-co-vinyl cinnamate (EVCIN) copolymers, before and after exposure to UV radiation, are reported. The purpose of these studies is to determine whether or not significant reaction (photo-crosslinking) of the cinnamate groups in EVCIN copolymers occurs upon UV exposure in the solid state as the concentration (fraction) of cinnamate groups is systematically reduced. By increasing the ethylene concentration in the EVCIN copolymers the cinnamate groups are “diluted” and progressively spaced apart in the copolymer. Somewhat surprisingly, we find that an EVCIN copolymer containing only 5 mole % vinyl cinnamate still undergoes a facile crosslinking in the solid state upon UV exposure. 相似文献