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1.
以对二氯苯为原料,经硝化、水合肼催化还原、Bamberger重排等反应合成了2,5-二氯-4-氨基苯酚;并对水合肼催化还原和Bamberger重排反应的条件进行了优化。在优化的条件下,2,5-二氯苯胲的收率达96.1%,2,5-二氯-4-氨基苯酚的收率达53.1%。该合成工艺具有反应周期短、条件温和、收率高和后处理简单等优点,有产业化前景。  相似文献   

2.
用芴和氯仿合成的9,9-二氯芴经水解得到9-芴酮。该工艺反应条件温和,收率达96.56%,产品纯度达99%以上。  相似文献   

3.
对甲氧基肉桂酸异辛酯合成新工艺   总被引:1,自引:0,他引:1  
曾庆友 《化学工程师》2007,21(10):13-15
用茴香醛、丙二酸二乙酯和异辛醇为主要原料,以L-脯氨酸/磷酸钾为催化剂,无水乙醇为溶剂,经Knoenenagel反应合成对甲氧基肉桂酸乙酯中间体,收率达83.7%。在对甲苯磺酸催化作用下,对甲氧基肉桂酸乙酯与异辛醇进行酯交换反应得到对甲氧基肉桂酸异辛酯,收率达92.3%。  相似文献   

4.
本文以对苯二酚为起始原料,经烷基化、硝化、还原等反应,合成了2,5-二甲氧基苯胺,三步反应收率分别为79.1%、93.8%和93.2%.通过正交实验考察了不同反应温度、反应时间、摩尔比等对还原收率的影响.实验确定的最佳工艺条件是:硫磺与硝基物摩尔比为4:1,反应温度为90~95℃,反应时间为8小时,还原反应收率达93.2%.目标产物结构经MS、1H NMR表征.  相似文献   

5.
本文以对苯二酚为起始原料.经烷基化、硝化、还原等反应,合成了2.5-二甲氧基苯胺,三步反应收率分别为79.1%、93.8%和93.2%.通过正交实验考察了不同反应温度、反应时间、摩尔比等对还原收率的影响.实验确定的最佳工艺条件是:硫磺与硝基物摩尔比为4:1.反应温度为90-95℃,反应时间为8小时,还原反应收率达93.2%.目标产物结构经MS、1H NMR表征.  相似文献   

6.
以丙烯酸乙酯为原料,经加成、取代、Dieckmann缩合反应、水解之后得到目标产物N-苄基-3-吡咯烷酮。对Dieckmann缩合反应进行了改进,采用钠砂为催化剂,反应收率由44.7%提高到64.0%,并对其它各步的反应条件进行了优化,3-苄胺基丙酸乙酯和3-(N-乙氧羰基亚甲基)苄胺基丙酸乙酯的单步收率分别为96%和93%,四步反应总收率达57.2%,该工艺简单、原料易得、操作简便、收率稳定,适合工业化生产。  相似文献   

7.
4-(4-氯苯基)环己醇及4-(4-氯苯基)环己酮的合成研究   总被引:1,自引:0,他引:1  
以氯苯、环己烯、乙酰氯为原料,通过Friedel-Crafts反应、Baeyer-Villiger反应、水解反应得到4-(4-氯苯基)环己醇。通过正交试验得到Friedel-Crafts反应和Baeyer-Villiger反应优化后的工艺条件。4-(4-氯苯基)环己醇总收率达12.9%,较文献收率提高了6%以上。所得醇经次氯酸钠氧化,得到4-(4-氯苯基)环己酮,氧化收率87%,产品的结构经1HNMR、GC-MS鉴定。  相似文献   

8.
除草剂双氟磺草胺的合成   总被引:1,自引:0,他引:1  
张梅凤  唐永军  刘伟 《农药》2012,51(4):249-250,256
[方法]以2,4-二氯-5-氟嘧啶为起始原料,经醚化反应、肼化反应、环合反应、苄硫醚化反应、异构化反应、氯氧化反应和酰胺化反应合成双氟磺草胺。[结果]以2,4-二氯-5-氟嘧啶计,产品总收率达66.7%,含量达97%,产品结构经氢谱核磁分析验证。[结论]该方法具有工艺路线合理、反应条件温合、原料易得、产品质量好、收率高、成本低等特点,适合于工业化生产。  相似文献   

9.
以3-氯丙烯和苯酚为原料,经O-烷化、C laisen重排,制备邻烯丙基苯酚,考察了几种常用反应溶剂及碱对烯丙基苯基醚收率的影响;通过单因素实验进一步考察了原料比、反应温度、反应时间对产物收率的影响。结果表明,以甲醇为溶剂时,加入氢氧化钠可提高苯酚反应活性,在n(苯酚)∶n(3-氯丙烯)=1∶1.2,反应温度60℃,反应时间4 h条件下,烯丙基苯基醚收率达65.0%,烯丙基苯基醚在190~220℃下回流反应7 h,邻烯丙基苯酚收率达81.2%。  相似文献   

10.
以廉价的商业化试剂5-溴-2-碘苯甲酸为原料,经Ullmann醚化、酸胺缩合、成盐等反应制备出醋酸氟卡尼,反应总收率达54.2%(以5-溴-2-碘苯甲酸计)。并对关键的Ullmann反应条件进行优化。结果表明:当以{[双-(1.10-菲啰啉铜)][三氟乙氧基]铜}为配体时 ,以DMF为溶剂,110℃反应12h。中间体收率达60.1%。改进工艺路线后醋酸氟卡尼总收率为54.0%,纯度为99.93%。中间体及产物经1H NMR、MS等确证。  相似文献   

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12.
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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16.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

17.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

18.
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   

19.
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   

20.
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   

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