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2-氯甲基-4-甲氧基-3,5-二甲基吡啶盐酸盐的合成 总被引:4,自引:0,他引:4
2,3,5 三甲基吡啶用双氧水/冰醋酸氧化制得2,3,5 三甲基吡啶 N 氧化物,收率91%;该氧化吡啶与发烟硝酸/浓硫酸反应得4 硝基 2,3,5 三甲基吡啶 N 氧化物,收率80 4%;将其与甲醇钠反应得到4 甲氧基 2,3,5 三甲基吡啶 N 氧化物,收率91%;4 甲氧基 2,3,5 三甲基吡啶 N 氧化物与乙酸酐反应得到2 乙酰基氧甲基 4 甲氧基 3,5 二甲基吡啶,收率66 6%;2 乙酰基氧甲基 4 甲氧基 3,5 二甲基吡啶在碱性条件下水解得2 羟甲基 4 甲氧基 3,5 二甲基吡啶,收率93%;再用氯化亚砜氯代制得2 氯甲基 4 甲氧基 3,5 二甲基吡啶盐酸盐,收率90 6%。通过TLC、IR、1HNMR对产物进行了表征。 相似文献
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以3-羟基吡啶为原料,高产率地获得了医药中间体2-氨基-5-甲氧基吡啶,同时对反应条件进行了优化,并第一次以高产率得到了2-氨基-5-甲氧基偶氮吡啶。 相似文献
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以5-溴-2-甲氧基吡啶为原料,经取代、过氧化、脱甲基化3步制备了5-甲磺酰基-1H-吡啶-2-酮.取代过程选用正丁基锂先与5-溴-2-甲氧基吡啶进行卤素-锂交换反应,再用二甲基二硫醚进行亲核取代,反应彻底且收率较高.过氧化过程选用间氯过氧苯甲酸作为过氧化剂,将甲硫基氧化为甲磺酰基,此步选用n(2-甲氧基-5-甲硫基吡啶)∶n(间氯过氧苯甲酸)=1.00∶2.50的投料比,有较好的收率.在脱甲基化过程中选用氢溴酸醋酸溶液进行脱甲基化,目标产物直接在醋酸中析出,提纯较为简便.目标产物的总收率为58.03%,其结构经1H NMR、13C NMR和IR确证.该方法操作简单,收率较高,易提纯,可大批量生产. 相似文献
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对新型质子泵抑制剂泰妥拉唑的关键中间体2-巯基-5-甲氧基咪唑并[4,5-b]吡啶的合成工艺进行了研究,以2,6-二氯吡啶为原料,先硝化得到2,6-二氯-3-硝基吡啶,然后经胺化得2-氨基-3-硝基-6-氯吡啶,再与甲醇钠反应得2-氨基-3-硝基-6-甲氧基吡啶,用铁粉还原得2,3-二氨基-6-甲氧基吡啶,最后与二硫化碳环化制得标题化合物。各步反应的最佳反应条件(反应温度,反应时间,摩尔收率)分别为,硝化: 110℃, 8 h, 79.3%; 胺化:室温, 10 h, 87.6%; 甲氧基化:65℃, 30min, 98.7%; 还原:回流, 3hrs; 环化:回流, 4hrs, 71.3%(还原及环化两步)。 标题化合物熔点与文献报道一致,并通过1H NMR进一步确证结构。 相似文献
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研究了以3-氯-5-甲氧基-2,6-二硝基吡啶为原料,通过甲氧化、硝化、氨化合成3-甲氧基-5,6-二氨基-2-硝基吡啶,该化合物的结构通过IR,1H NMR,MS和元素分析进行了表征,确认为目标化合物。分析了3-甲氧基-5-氯-2,6-二硝基吡啶的氯基和硝基的反应活性。 相似文献
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以氨水为胺化剂,KMnO4为氧化剂,在不同反应条件下实现2-甲氧基-5-硝基吡啶6位的氧化胺化反应,探讨了溶胡类型、氨水浓度等反应条件对目标化合物产率影响。结果表明,以KMnO4,NH3/DMSO,H2O为氧化胺化体系,在30℃条件下持续通入氨气,反应时间4h,2-氨基-6-甲氧基-3-硝基吡啶收率最高达到92.5%。 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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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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
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Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US
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
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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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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
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
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
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