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5-壬基水杨醛是合成5-壬基水杨醛肟的重要中间体,5-壬基水杨醛肟作为铜萃取剂在工业上有很多应用。以4-壬基酚、六次甲基四胺为原料,醋酸为溶剂,经Duff反应合成了5-壬基水杨醛。相对其他合成5-壬基水杨醛的方法,采用Duff反应来合成具有操作简便、反应周期较短、产物单一且容易进行提纯等优点。通过对原料的物质的量之比、反应时间、反应温度等因素对目标产物收率的影响,确定了合成5-壬基水杨醛适宜的反应条件:n(4-壬基酚)∶n(六次甲基四胺)=1∶2,反应温度为90 ℃,醋酸为溶剂,反应6 h。在上述条件下,以4-壬基酚计,目标产物的收率为98.7%,液相色谱纯度为92.0%,产物经1H-NMR表征,其结构目标产物一致。 相似文献
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新型8-羟基喹啉衍生物的合成 总被引:1,自引:0,他引:1
以2-甲基-8-羟基喹啉为原料,在乙酸酐作溶剂的条件下,分别与苯甲醛、水杨醛、糠醛反应,合成了3种新型的8-羟基喹啉衍生物,考察了各实验条件对合成产物收率的影响,并确定其优化实验条件;产:物通过元素分析、IR,UV,^1H NMR等对其进行结构表征。 相似文献
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Poly(ethylene glycol) (PEG) propionaldehyde is an important polymer derivative used in protein modification; it is usually synthesized by the Williamson reaction of 3‐chloropropionaldehyde diethyl acetal (CPADA) with PEG alkoxide followed by hydrolysis to deprotect the aldehyde group. However, the side reaction of the Williamson reaction has been a severe drawback leading to a low‐aldehyde‐content product. In this study, we established a kinetic model to depict the competition of the Williamson reaction and its side reaction. Based on a kinetic analysis, experiments were performed to systemically investigate the influence of the process parameters on the yield of PEG aldehyde, including the reaction solvents, reaction temperature, and molar equivalents of CPADA. The best reaction solvent was determined to be dioxane because the conversion of methoxy pol(ethylene glycol) in dioxane was higher than that in other solvents and because dioxane has low toxicity and is easily handled. The reaction temperature was set as the refluxing point of dioxane to effectively convert PEG into its alkoxide. The equivalents of CPADA were optimized to be 15 to obtain a quantitative yield of mPEG propionaldehyde and avoid wasting the reagent. The quantitative yield of mPEG propionaldehyde was achieved under these optimum conditions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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以氯乙酰化聚苯乙烯(PS-Acyl-Cl)代替氯甲基化聚苯乙烯作为载体,引入乙二胺(EDA)和己二胺(HMD)得到2种胺基树脂。考察了反应时间、油浴温度、物料比、溶剂体系等对胺化反应的影响,在最佳反应条件下,乙二胺和己二胺树脂的担载量分别达到1.60 mmol/g和2.6 mmol/g。将2种胺基树脂进行比较:在相同条件下,制备的己二胺树脂的担载量明显高于乙二胺树脂。该方法避免了氯甲基化法存在的弊端,并消除了烷基化引起的二次交联及多取代等副反应。制备的胺基树脂可以作为一个活性中间体,进一步衍生化制备多种功能介质。 相似文献
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探讨乙酰水杨酸微型化合成的最佳实验条件。以浓硫酸作催化剂,用乙酸酐与水杨酸进行酰化反应制备乙酰水杨酸,改变反应条件进行实验,重点考察了反应物摩尔数比、反应温度、反应时间及催化剂等条件对反应的影响。乙酰水杨酸微型化合成的最佳实验条件是:乙酸酐和水杨酸的摩尔数比为3∶1,反应温度60~80℃,以浓硫酸作催化剂,反应时间3~5 min。 相似文献
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由乙二胺和对甲苯磺酰氯反应制得N,N′-双(对甲苯磺酰基)乙二胺。此步最佳工艺条件为:n(对甲苯磺酰氯)∶n(乙二胺)=2.2∶1,反应溶剂为苯,反应温度为40~45℃,反应时间为6h,收率80%。由丙烯酸甲酯和溴反应制得α,β-二溴丙酸甲酯,收率为88%。再由上述二种中间体反应合成标题化合物,此步省略了N,N′-双(对甲苯磺酰基)乙二胺的二钠盐制备,收率为73%。 相似文献
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Fabrizio Cavani Luca Maselli Sauro Passeri Johannes A. Lercher 《Journal of Catalysis》2010,269(2):340-350
Reactions of phenol and methanol catalyzed by MgO have been explored by kinetic measurements and in situ IR spectroscopy combined with computational studies of sorbed molecules. On MgO, methanol partly transforms to formaldehyde above 250 °C. Adsorbed phenol forms phenolate species, and the energetically preferred mode of adsorption leads to an almost orthogonal orientation of the aromatic ring with respect to the catalyst surface. All molecules involved adsorb preferably at the corner sites of MgO (three-co-ordinated Mg atoms). The main reaction products are anisole and o-cresol, the latter dominating above 300 °C. At very low conversions, salicylic aldehyde is observed as primary reaction product, being rapidly transformed to o-cresol. It is only observed during the initial accumulation of adsorbed species on the catalyst surface, but not under steady-state conditions on a fully covered catalyst surface. Therefore, o-cresol formation starts with the reaction between phenol and formaldehyde to salicylic alcohol, which in turn is rapidly transformed to salicylic aldehyde and subsequently to o-cresol. Salicylic aldehyde may also form via the bimolecular disproportionation of salicylic alcohol to o-cresol and aldehyde. The parallel reaction to o-cresol, not involving the formation of salicylic aldehyde as intermediate, proceeds via the reduction of salicylic alcohol to o-cresol by formaldehyde. The identified mechanism may open new synthetic approaches for the production of functionalized phenol derivatives and, even more importantly, for the defunctionalization of substituted phenols potentially available at large scale from deconstructed lignin. 相似文献
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水杨酸甲酯的加压合成工艺研究 总被引:1,自引:0,他引:1
以水杨酸和甲醇为原料,对甲苯磺酸催化作用下合成了水杨酸甲酯,考察了酸醇摩尔比、反应温度、反应时间及反应压力对酯收率的影响。结果表明,较佳合成工艺条件为:n(水杨酸)∶n(甲醇)摩尔比=1∶5,反应温度120℃,反应时间5 h,反应压力162 kPa,在此条件下,酯收率接近90.0%。产品经FT-IR确定结构,用气相色谱检测,产品纯度达到99.5%。 相似文献