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在无水碳酸钾存在下,N,N-二甲基甲酰胺(DMF)为溶剂,由N-甲基氯乙酰胺和4-苯氧基苯酚反应,制备了一种新的化合物N-甲基-2-(4-苯氧基苯氧基)乙酰胺,该化合物已取得中国发明专利ZL2004100.84390.1。考察了反应温度、反应时间、物料摩尔比对化合物收率的影响,确定了合成工艺条件为:反应温度75~85℃,反应时间4 h,n(N-甲基氯乙酰胺)∶n(4-苯氧基苯酚)=1.2∶1.0。在此条件下,N-甲基-2-(4-苯氧基苯氧基)乙酰胺的产率达85%以上。用N-甲基-2-(4-苯氧基苯氧基)乙酰胺与苯氧威分别对蔬菜蚜虫进行了防治实验,两化合物药效接近。化合物的结构经IR、MS1、HNMR和元素分析进行了表征。 相似文献
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本文对N,N-二甲基乙二胺合成方法进行了综述,并对以乙醇胺为原料经氯化氯乙胺合成N,N-二甲基乙二胺的合成路线进行了深入研究,取得了以乙醇胺计总收率达70%以上的良好结果。 相似文献
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蚊蝇醚的合成方法改进 总被引:4,自引:0,他引:4
以4-苯氧基苯酚,环氧丙烷和2-氯吡啶为原料,通过两步反应合成蚊蝇醚。确定了合成蚊蝇醚的最佳工艺条件为:第一步:n(4-苯氧基苯酚)∶n(环氧丙烷)∶n(氢氧化钾)=1∶3.0∶0.3,反应温度40℃,反应时间3.5 h,1-(4-苯氧基苯氧基)-2-丙醇收率可达92.5%;第二步:n(1-(4-苯氧基苯氧基)-2-丙醇)∶n(氢氧化钾)∶n(2-氯吡啶)=1∶3.5∶1.4;反应时间4 h,反应温度:120℃,蚊蝇醚收率可达86.4%。用IR1、H NMR、MS对蚊蝇醚结构进行了表征。 相似文献
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以二苯醚和苯甲酰氯为原料,经酰基化合成4-苯氧基二苯甲酮,然后再经Beayer-villyger氧化以及碱性水解合成4-苯氧基苯酚。主要考察Beayer-villyger氧化反应中反应温度、反应时间、原料配比等因素对产物收率的影响。结果表明,在40°C7、h、n(过氧化氢)∶n(硫酸)∶n(4-苯氧基二苯甲酮)=3.0∶4.0∶1.0条件下,Beayer-villyger氧化反应的收率最高可达91.4%。在上述条件下,经三步反应,得到4-苯氧基苯酚,其总收率达80%以上。经熔点、红外光谱及元素分析确定产物为4-苯氧基苯酚。 相似文献
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采用水相体系直接合成得到高纯度的1,2-二苯氧基乙烷,在优化工艺条件下,以1,2-二溴乙烷和苯酚为基本原料,KOH为碱,1,2-二苯氧基乙烷摩尔收率达75%,产品气相色谱纯度达99%,且完成了10 kg/批的扩大合成实验评价,效果稳定。最优合成工艺为:反应时间25 h,w(KOH)=50%的水溶液,n(KOH)∶n(苯酚)∶n(1,2-二溴乙烷)=3.0∶3.0∶1.0,反应温度60℃。在该条件下,产物中杂质的生成量较少。 相似文献
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付春 《精细与专用化学品》2004,12(14):19-21
通过对苯肼的合成工艺进行改进 ,高收率地合成了高纯度苯肼 ,产品纯度为 99% (GC)以上 ,联苯胺浓度小于 0 0 0 1 5 % (HPLC) ,苯胺小于 0 1 % (HPLC) ,苯酚小于 0 0 5 % (HPLC) ,总收率由 70 %提高到 75 %。 相似文献
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OU Onuwaje 《Nutrient Cycling in Agroecosystems》1983,4(4):357-360
The effect of various combinations of N, P, K and Mg fertilizer on yield of rubber over a 3 year period is discussed.N, K and Mg increased yield consistently over the period. The average annual increase in yield over control as a result of application of N, K and Mg were 11%, 3% and 9% respectively; where the effect of P was positive it was negligible.Combined applications of N, K and Mg produced increases that were higher than when they were applied individually. The N1 K2 combination produced a mean annual increase of 18% over N0 K0, while N1 Mg1 increased yield by an average of 26% annually over N0 Mg0.N, K and Mg are thus considered as generally required by the rubber trees. 相似文献
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At 600 °C, NOx catalyzes the partial oxidation of both methane and ethane by dioxygen to form formaldehyde. The yield of oxygenates from methane is over 11. The yield increases to over 16 when 0.7% of ethane is added to the gas mixture. The yield of oxygenates from ethane is over 24. A catalytic cycle involving NO2 as the C–H activating species is proposed. 相似文献
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Yu-Yen Linko Xiao Yan Wu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1996,65(2):163-170
Two distinct lipase forms were obtained from Candida rugosa lipase by Phenyl Sepharose hydrophobic interaction and DEAE Sepharose ion exchange chromatography, L1 at 45% yield and L2 at 4·7% yield. Both purified lipases were able to catalyse esterification of 1-butanol and oleic acid and trans-esterification of 2-ethyl-1-hexanol and rapeseed oil. Lipase L1 gave a 98% yield for esterification over 12 h and a 99% conversion of rapeseed oil for trans-esterification over 24 h. The minor fraction L2 gave a 97% yield for esterification over 30 h and only a 79% conversion for trans-esterification over 24 h. The superiority of fraction L1, especially in trans-esterification, could be clearly shown by reversed phased HPLC analysis. Sodium deoxycholate treatment of the purified main lipase L1 considerably improved the initial rate in both esterification and trans-esterification. 相似文献