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2-甲氧基-4-丙烯基苯基苄基醚的相转移催化合成研究 总被引:6,自引:1,他引:5
在相转移催化剂存在下,以2-甲氧基-4-丙烯基苯酚、氯化苄为原料合成2-甲氧基-4-丙烯基苯基苄基醚,分别研究了反应温度、反应时间、原料配比、催化剂用量等条件对合成反应的影响.确定了最佳工艺条件。该方法合成2-甲氧基-4-丙烯基苯基苄基醚的最佳工艺条件是:反应温度95℃;反应时间2h;n(2-甲氧基-4-丙烯基苯酚):n(氯化苄)=1:1,05;n(2-甲氧基-4-丙烯基苯酚):n(氢氧化钾)=1:1.10;催化剂=5.89%(相对于2-甲氧基-4-丙烯基苯酚质量分数),2-甲氧基-4-丙烯基苯基苄基醚的收率可达到92.52%以上,产品纯度98.5%。 相似文献
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2-溴乙氧基苯的相转移催化合成研究 总被引:1,自引:0,他引:1
在四丁基溴化铵相转移催化剂存在下,以苯酚、1,2-二溴乙烷为原料合成2-溴乙氧基苯,分别研究了反应温度、反应时间、原料配比、催化剂用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成2-溴乙氧基苯的最佳工艺条件是:反应温度100°C;反应时间6 h;n(苯酚)∶n(1,2-二溴乙烷)=1∶1.15;n(苯酚)∶n(氢氧化钠)=1∶1.15;溶剂用量为40 mL(相对于0.15 mol苯酚),催化剂用量为1 g(相对于0.15 mol苯酚),2-溴乙氧基苯的收率可达到88.9%以上,产品纯度98.5%。 相似文献
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在微波辐射条件下,以苯酚、氢氧化钾和正溴丁烷为原料,聚乙二醇400为相转移催化剂,无水乙醇为溶剂,合成了正丁基苯基醚.通过测定折射率和红外光谱分析对产物进行了表征.研究了反应物的摩尔比、催化剂与溶剂的用量、微波辐射功率和微波辐射时间等对产物收率的影响.结果表明,当n(苯酚)∶n(氢氧化钾)∶n(正溴丁烷)∶n(PEG-400)=1∶2.0∶3.0∶0.08、乙醇用量为20 mL、微波辐射功率为160 W、辐射时间为4 min时,正丁基苯基醚的收率可达97.58%. 相似文献
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聚乙二醇催化合成正丁基苯基醚 总被引:4,自引:0,他引:4
以乙醇为溶剂、聚乙二醇为相转移催化剂,氢氧化钾为碱,从正丁基溴和苯酚合成了正丁基苯基醚。当0.1mol苯酚,0.3mol正丁基溴,乙醇为溶剂,在氢氧化钾和聚乙二醇400存在下,加热2h正丁基苯基醚收率达96.7%。 相似文献
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以对氰基苯酚和1,3-二溴丙烷为原料,四丁基溴化铵为催化剂,制备1,3-二(对氰基苯氧基)丙烷。考察了催化剂的用量、原料配比、温度和时间对收率的影响。优化条件为:n(对氰基苯酚):n(1,3-二溴丙烷)=2.3:1.0,凡(四丁基溴化铵):n(对氰基苯酚)=1:12.5,醚化反应温度为50℃,反应时间为8h,1,3-二(对氰基苯氧基)丙烷收率达到71%。避免了有机溶剂的使用及后序处理。 相似文献
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It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples. 相似文献
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J. R. Aldrich S. P. Carroll W. R. Lusby M. J. Thompson J. P. Kochansky R. M. Waters 《Journal of chemical ecology》1990,16(1):199-210
Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA. 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria. 相似文献
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2008~2009年世界塑料工业进展 总被引:4,自引:1,他引:3
中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2010,38(3)
收集了2008年7月~2009年6月世界塑料工业的相关资料,介绍了2008~2009年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、环氧树脂、不饱和聚酯树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。 相似文献
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ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究 总被引:15,自引:0,他引:15
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。 相似文献
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