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1.
光稳定剂二苯甲酮合成新工艺研究   总被引:1,自引:0,他引:1  
以苯甲酰氯、三氯化苄和苯为原料合成二苯甲酮,分别研究了反应温度、反应时间、原料配比、催化剂用量、溶剂的用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成二苯甲酮的最适宜的工艺条件是:反应温度120℃、反应时间12 h、n(苯甲酰氯)∶n(苯)=1∶1.7,n(苯甲酰氯)∶n(三氯化苄)=7.35∶1,催化剂用量为4.25 g(相对于0.588 mol苯甲酰氯),二苯甲酮的收率可达到94.54%以上,产品纯度二苯甲酮99.5%。  相似文献   

2.
合成了硝酸正丁铵、醋酸正丁铵、醋酸二乙铵3种铵型离子液体,采用1HNMR对其结构进行了表征。以上述铵型离子液体为催化剂,二苯甲酮和80%水合肼为原料,制备了二苯甲酮腙,产物结构经1HNMR和IR确定。考察了离子液体种类、用量、原料比例以及反应时间等因素对合成二苯甲酮腙产率的影响,优化了反应工艺。研究结果表明,以18.2 g的二苯甲酮及9 mL的水合肼为原料,5 mL的硝酸正丁铵为催化剂,乙醇为溶剂,80℃反应9 h,二苯甲酮腙的产率98.16%。与传统方法相比,该优化条件下获得了较高产率。  相似文献   

3.
在相转移催化剂存在下,以2,4-二羟基二苯甲酮、丙烯酸(2′-氯乙基)酯为原料合成2-羟基-4-丙烯酰氧乙氧基二苯甲酮,分别研究了反应温度、反应时间、原料配比、催化剂用量、阻聚剂用量等条件对合成反应的影响,确定了最佳工艺条件是:反应温度110℃;反应时间6h;n(2,4-二羟基二苯甲酮)∶n(丙烯酸(2′-氯乙基)酯)∶n(氢氧化钠)=1∶1.15∶1.2;溶剂用量为40mL,催化剂用量为0.8g、阻聚剂用量0.6g(相对于0.1 mol 2,4-二羟基二苯甲酮),产品收率可达到85.71%。  相似文献   

4.
以合成的芳香性季铵型离子液体为催化剂,以叔丁基苯和乙酰氯为原料合成了对叔丁基苯乙酮,并与无水三氯化铝催化反应进行了对比,考察了催化剂用量、反应时间、溶剂等因素对反应的影响。结果表明:以季铵型离子液体作催化剂,以二氯甲烷为溶剂,叔丁基苯为0.3mol,n(叔丁基苯)∶n(乙酰氯)∶n(离子液体)=1∶1∶2.5,反应温度为10℃,反应时间为2h时,对叔丁基苯乙酮产率可达87.9%。  相似文献   

5.
医药中间体丙酮缩氨基脲合成研究   总被引:1,自引:0,他引:1  
王树清  高崇 《化学世界》2006,47(9):555-557,516
以水合肼、尿素、丙酮为原料,直接反应合成丙酮缩氨基脲,分别研究了反应温度、反应时间、原料配比、溶剂用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成丙酮缩氨基脲的最佳工艺条件是:水合肼和尿素反应温度100℃,反应时间7 h;氨基脲与丙酮反应温度55℃,反应时间2 h;n(水合肼)∶n(尿素)∶n(丙酮)=1∶1.6∶3。丙酮缩氨基脲的收率达到97.19%,产品纯度达到98.5%。  相似文献   

6.
梁红冬  曾运高 《应用化工》2011,40(2):281-282,286
以D72树脂为催化剂,丁醛和乙二醇为原料,合成丁醛缩乙二醇。考察了原料配比、催化剂用量、反应时间和带水剂用量对反应的影响。实验表明,丁醛乙二醇缩醛合成反应的最佳条件是:n(丁醛)∶n(乙二醇)=1∶2,D72固体树脂用量为原料总质量的10%,环己烷用量10 mL,回流温度为130℃,反应时间2.5 h,丁醛缩乙二醇的收率达94.2%。且催化剂可以重复使用。  相似文献   

7.
《应用化工》2015,(8):1482-1484
以大豆油为原料,碱性离子液体为催化剂,制备生物柴油,研究反应温度、醇油摩尔比、反应时间和碱性离子液体的用量对生物柴油产率的影响。结果表明,碱性离子液体催化大豆油制备生物柴油的最佳工艺条件是:n(甲醇)∶n(大豆油)=12∶1,反应温度55℃,反应时间1.5 h,离子液体用量2.5%。在该工艺条件下,生物柴油产率41.3%。  相似文献   

8.
《应用化工》2022,(8):1482-1484
以大豆油为原料,碱性离子液体为催化剂,制备生物柴油,研究反应温度、醇油摩尔比、反应时间和碱性离子液体的用量对生物柴油产率的影响。结果表明,碱性离子液体催化大豆油制备生物柴油的最佳工艺条件是:n(甲醇)∶n(大豆油)=12∶1,反应温度55℃,反应时间1.5 h,离子液体用量2.5%。在该工艺条件下,生物柴油产率41.3%。  相似文献   

9.
合成二苯甲酮的新方法   总被引:5,自引:0,他引:5  
陈忠秀 《精细化工》2003,20(3):179-181
研究了二苯甲烷(DPM)在乙醚溶剂中的氧化反应,提出了二苯甲酮合成新方法。以w(HNO3)=68%硝酸做氧化剂,NH4VO3做催化剂,在乙醚溶剂中氧化二苯甲烷得到定量的二苯甲酮(BP)。较适宜的反应条件为:n(NH4VO3)∶n(DPM)=0 1∶1,w(HNO3)=68%的硝酸用量为5mL/mmolDPM,乙醚用量5mL/mmolDPM,反应温度80℃,反应时间3h。实验表明,乙醚在该反应中起重要的作用。在其他条件相同的情况下,不加乙醚,反应无氧化产物生成,只生成二苯甲烷的硝化产物。  相似文献   

10.
通过两步合成法制备得到酸性离子液体1-(4-磺酸基)丁基-3-甲基咪唑四氟硼酸盐,考察了投料物质的量比、反应时间等不同反应因素对其合成的影响,得到最佳反应条件即为投料物质的量比n(N-甲基咪唑)∶n(1,4-丁烷磺内酯)=0.08∶0.1、反应时间为6.5h、投料物质的量比n(磺基内盐)∶n(氟硼酸)=0.08∶0.1,并对其表征确证,将其作为酸性催化剂,用于风信子素的合成.以常规试剂乙缩醛和苯乙醇为原料,通过醇交换法,一步合成了风信子素,并对其进行正交试验研究.结果表明,合成风信子素的最佳条件为:反应时间6h、催化剂用量0.6 g、投料物质的量比n(苯乙醇)∶n(乙缩醛)=1∶5、反应温度40℃,收率81.96%.影响风信子素合成收率因素的主次顺序为:反应温度>反应时间>投料物质的量比n(苯乙醇)∶n(乙缩醛)>催化剂使用量,产物结构通过GC-MS和1HNMR进行了表征.  相似文献   

11.
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   

12.
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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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

18.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008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、不饱和聚酯树脂、环氧树脂)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   

19.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006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生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。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(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

20.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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