共查询到19条相似文献,搜索用时 93 毫秒
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无溶剂条件下用微波辐射及相转移催化合成香茅腈 总被引:1,自引:0,他引:1
以香茅醛为原料,在微波辐射及相转移催化剂聚乙二醇-600催化作用下由SiO2/Na2CO3-NaOH混合碱促进的无溶剂一步法直接制备香茅腈。确定的最佳反应条件是:香茅醛与盐酸羟胺摩尔比1∶1.4~1∶1.6;对应每mmol香茅醛,SiO2的用量为0.25~0.30 g;催化剂为PEG-600和Na2CO3-NaOH(7∶3,n/n),彻底研磨后用微波辐射功率为730 W,反应时间为4~5 min,制备效果最佳。在此条件下从香茅醛制备香茅腈的平均得率达85.05%。 相似文献
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PEG相转移催化法合成香茅腈 总被引:3,自引:0,他引:3
研究了用PEG作相转移催化剂由香茅醛合成香茅腈的工艺条件,产品纯度96.7%,产率87.3%,nD^201.4491;最佳实验条件为:用PEG-400和KOH作催化剂,物料比为香茅肟:PEG-400;氢氧化钾=100:15:10(mol),在125℃下反应2.5h,并用适量甲苯作带水剂。 相似文献
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以香茅醛为原料,经二甲胺羰基保护、硫酸催化条件下甲氧基化、氢氧化钠中和合成甲氧基香茅醛。考察了反应温度、反应时间、投料比等工艺条件对产品收率的影响。实验研究得到了最优的合成工艺条件为:胺化反应二甲胺与香茅醛摩尔比为2∶1,反应温度10~15℃,反应时间3 h。甲氧基化反应硫酸浓度为100%,甲醇∶硫酸∶烯胺的摩尔比为15∶5∶1,反应温度15~18℃,反应时间2 h。产品总收率47.6%。反应工艺简单,条件温和,原料易得,便于工业化。产品经IR1、H NMR、GC/MS、元素分析确证结构。 相似文献
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柠檬桉叶油的主要成分是香茅醛。文中介绍了采用02型催化剂由香茅醛选择性加氢制香茅醇的方法,分别考察了温度、压力、搅拌转速、原料纯度对反应的影响,并确定了相应的工艺操作条件。 相似文献
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甲氧二氢香茅醛的合成 总被引:2,自引:0,他引:2
甲氧二氯香茅醛是一种国内尚未见生产的新香料。本文报道了以香茅醇为起始原料经加成、氧化反应合成甲氧二氢香茅醛的合成工艺路线,该路线具有操作简便,反应条件温和及无需特殊设备的优点。 相似文献
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在改性骨架镍钠化剂上柠檬桉叶油选择加氢制备香茅醇 总被引:1,自引:0,他引:1
研制了适用于香茅承较低压力下选择加氢香茅醇的改性骨架镍催化剂,香茅醛的转化率达99.5%以上,选择性达99.5%以上,加氢的适宜温度为75℃,压力为2MPa,分别考察了向反应液中添加不同助催化剂及其不同用量对反应的转化率和选择性的影响,并确定了相应的工艺操作条件。 相似文献
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Passerini反应是一类重要的多组分反应,它可以快速的合成许多结构复杂的药物中间体,文章以苯甲醛,2-异丁腈和硝基甲烷为原料,氯化锌为催化剂,在微波作用下,发展新的多组分Passerini反应。 相似文献
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以2,5-二氯苯腈和活性氟化钾为原料,环丁砜为溶剂,四丁基氯化铵为催化剂合成2-氟-5-氯苯腈。最佳条件为n2,5-氯苯腈:n碱性氟化钾=1:3.0,n2,5-二氯苯腈:n环丁砜=1:5.0,环丁砜的回流温度215~240℃,反应时间6h。产品的平均收率可达88.39%。 相似文献
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Lisa N. Yee Casimir C. Akoh Robert S. Phillips 《Journal of the American Oil Chemists' Society》1997,74(3):255-260
Pseudomonas sp. lipase PS was immobilized by adsorption and tested for its ability to catalyze the synthesis of citronellyl butyrate
and geranyl caproate by transesterification in n-hexane. The reaction parameters investigated were: enzyme load, effect of substrate concentration, added water, temperature,
time course, organic solvent, pH memory, and enzyme reuse. Yields as high as 96 and 99% were obtained for citronellyl butyrate
and geranyl caproate, respectively, with 300 units (approx. 15% w/w of reactants) of lipase PS. Increasing amounts of terpene
alcohol inhibited lipase activity, while excess acyl donor (triacylglycerol) concentration enhanced ester production. Optimal
yields were obtained at temperatures from 30–50°C after 24-h incubation time. Yields of 90 and 99% were obtained for citronellyl
and geranyl esters, respectively, with 2% added water. Solvents with log P values ≥ 2.5 showed the highest conversion yields. pH 7 and 6–8 seemed to be ideal for citronellyl butyrate and geraniol
caproate, respectively. The lipase remained active after reusing 12 times. 相似文献
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介绍了N-羟甲基丙烯酰胺(N-AM)硫化体系在丁腈手套制备中的应用。实验采用羧基丁腈胶乳(XNBRL)为原料,以N-AM为硫化剂、二丁基二硫代氨基甲酸锌(Bz)为促进剂、ZnO为硫化活性剂,经过预硫化、硫化、干燥等过程制得羧基丁腈胶膜。通过测试胶膜性能,研究了A(N-MA)、B(ZnO)、C(Bz)配比等因素对胶膜物理机械性能的影响,发现C(BZ)是影响胶膜物理性能的主要因素,其次是A(N-MA)和B(ZnO)。研究最终确定了最佳硫化体系配比A:B:C为3.5:2:1。 相似文献
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发展合成橡胶延伸加工技术 总被引:1,自引:0,他引:1
从我国合成橡胶企业单一原料型生产模式的转型目标出发,重点对丁腈橡胶、乙丙橡胶和热塑性弹性体等的延伸加工技术以及废橡胶的综合利用技术作了文献调研,并根据国内橡胶制品的市场需求,对延伸加工技术系列的开发提出了相应的建议。 相似文献
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The syntheses of geranyl acetate and citronellyl acetate by alcoholysis reaction catalyzed by immobilized lipase from Mucor miehei was studied for the first time in a solvent-free system. Reactions were carried out at a terpene alcohol/acyl donor molar
ratio of 1:5 with Lipozyme at 10% of the total weight of the reactants in a solvent-free system. Incubations were carried
out at 55 to 60°C for ethyl and butyl acetates as acyl donors, whereas for methyl acetate the incubation temperature was 40
to 45°C. Excess concentration of acyl donor increases the percentage of geranyl acetate and citronellyl acetate, while excess
of terpene alcohol concentration decreases the same. Yields from 75 to 77% molar conversion (90 to 98% conversion, w/w) were
obtained after 8 to 28 h of reaction time. 相似文献
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Maleimide and 2‐aminobenzonitrile (MIan)‐based benzoxazine has been synthesized and characterized. MIan contains imide, oxazine, and nitrile functional groups that can react almost simultaneously, leading to complicated reaction mechanisms. For understanding the fundamental polymerization mechanism, the model benzoxazine compound is synthesized. The ortho‐nitrile group in the model compound undergoes cyclization reaction, producing the thermally stable six‐membered ring species resulting in the excellent thermal properties of the material. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献