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1.
硼氢化锌还原苯乙酰胺的研究   总被引:1,自引:0,他引:1  
以硼氢化锌还原苯乙酰胺为苯乙胺,探讨了溶剂、反应时间及反应温度对苯乙胺收率的影响.确定苯乙酰胺最佳还原反应条件为:V(甲苯)∶V(THF)=3∶7、反应时间为4 h、反应温度为95℃,此时苯乙胺收率可达84.8%.  相似文献   

2.
N,N-二甲基乙酰胺是应用广泛的高沸点、非质子化溶剂,采用反应精馏技术合成N,N-二甲基乙酰胺,改进了传统的醋酸法工艺,考察了催化剂质量分数、回流比、反应温度和二甲胺/醋酸摩尔比等因素对N,N-二甲基乙酰胺收率的影响。在单因素实验的基础上,通过响应面分析实验确定反应精馏合成N,N-二甲基乙酰胺的最佳工艺条件为:催化剂质量为醋酸质量的3%,回流比为2.8∶1,反应温度为172℃,二甲胺/醋酸摩尔比为1.4∶1,此时,N,N-二甲基乙酰胺的收率可达93.34%。  相似文献   

3.
以N-甲基乙酰胺、醋酸乙烯酯为原料,以氢氧化钾为催化剂合成了N-乙烯基-N-甲基乙酰胺。对影响反应的各因素进行了考察,确定了最佳工艺条件为:N-甲基乙酰胺、醋酸乙烯酯、氢氧化钾物质量的比为1:1.1:0.012,加成反应温度控制在10℃C左右,产物收率达到81%:  相似文献   

4.
采用SnCl4·5H2O为催化剂催化2-萘酚、苯甲醛和乙酰胺的三组分一锅法类Ritter反应合成了1-乙酰胺基苯甲基-2-萘酚(AAN).考察了原料配比、催化剂用量、反应温度和反应时间等因素对AAN收率的影响,确定了适宜反应条件为:n(2-萘酚)∶n(苯甲醛)∶n(乙酰胺)=1∶1.4∶1,催化剂用量为反应物总质量的6%、85℃反应35 min,AAN的收率可达96.2%.该合成工艺路线简捷,催化剂价廉易得,催化活性高,使用方便,反应条件温和,收率可观.  相似文献   

5.
采用SnCl_4·5H_2O为催化剂催化2-萘酚、苯甲醛和乙酰胺的三组分一锅法类Ritter反应合成了1-乙酰胺基苯甲基-2-萘酚(AAN)。考察了原料配比、催化剂用量、反应温度和反应时间等因素对AAN收率的影响.确定了适宜反应条件为:n(2-萘酚):n(苯甲醛):n(乙酰胺)=1:1.4:1,催化剂用量为反应物总质量的6%、85℃反应35min,AAN的收率可达96.2%。该合成工艺路线简捷,催化剂价廉易得,催化活性高,使用方便,反应条件温和,收率可观。  相似文献   

6.
分别采用间氯甲苯、N-间甲苯基乙酰胺、间甲基苯胺和2-甲基-4-氯苯甲腈等不同的起始原料来合成标题化合物,并探讨了各条反应路线的条件、收率及工业生产的可行性,从而确定了以N-间甲苯基乙酰胺为原料的合成路线是一条较佳工业合成工艺路线,其总收率为32.3%.  相似文献   

7.
以N-甲基乙酰胺、醋酸乙烯酯为原料,N,N-二甲氨基吡啶(DMAP)为催化剂,合成N-甲基-N-乙烯基乙酰胺。对影响反应的各种因素进行了考察,确定了最佳反应条件为:反应温度65℃,反应时间12h,催化剂与N-甲基乙酰胺物质的量比为0.55。在此条件下,N-甲基-N-乙烯基乙酰胺收率为87.6%,催化剂可回收套用12次。  相似文献   

8.
以2-硝基-4-乙酰氨基苯甲醚为原料合成N-(3-氨基-4-甲氧基苯基)乙酰胺,考察了铁粉用量、冰醋酸用量和水量等对N-(3-氨基-4-甲氧基苯基)乙酰胺收率的影响.确定了最佳工艺条件n(2-硝基-4-乙酰氨基苯甲醚)∶n(铁粉)∶n(冰醋酸)∶n(水)=1∶2.4∶0.29∶40.8,反应时间为3 h.此条件下N-(3-氨基-4-甲氧基苯基)乙酰胺的收率达91.9%,纯度达99.9% (HPLC) .  相似文献   

9.
奈非西坦药物的合成研究   总被引:1,自引:0,他引:1  
以碳酸钠为缚酸剂,摩尔比为1︰1的2,6-二甲基苯胺与氯乙酰氯反应合成了中间体2-氯-N-(2,6-二甲基苯基)乙酰胺;在强碱乙醇钠作用下,2-吡咯烷酮再与2-氯-N-(2,6-二甲基苯基)乙酰胺经亲核取代合成了目标化合物奈非西坦。探讨了影响中间体和奈非西坦产率的因素,在乙醇钠、2-氯-N-(2,6-二甲基苯基)乙酰胺和2-吡咯烷酮的摩尔比为2︰1︰2、反应时间为2 h的较佳工艺条件下,产品总收率达81%。  相似文献   

10.
二氯乙酸甲酯与甲胺反应,制备了中间体N-甲基二氯乙酰胺。在无水碳酸钾存在下,以N,N-二甲基甲酰胺(DMF)为溶剂,中间体与4-苯氧基苯酚反应得到目的产物。着重考察了反应温度、反应时间、物料投料比对目的产物收率的影响,从而确定了产物的合成工艺条件为:反应温度85°C,反应时间4h,物料投料比n(N-甲基二氯乙酰胺)∶n(4-苯氧基苯酚)=1.0∶2.2。在此条件下,产物的收率达82%以上。经IR、MS、1H NMR确定为N-甲基-2,2-二(4-苯氧基苯氧基)乙酰胺。  相似文献   

11.
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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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   

14.
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   

15.
2008~2009年世界塑料工业进展   总被引:4,自引:1,他引: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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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   

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