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1.
(S)-N-保护的2-氨基-3-(二乙氧膦酰基)丙酸乙酯是用于制备L-2-氨基-3-膦酰基丙酸的重要中间体。报道了立体选择性合成(S)-N-保护的2-氨基-3-(二乙氧膦酰基)丙酸乙酯的方法,以N-保护的L-丝氨酸为原料,经Mitsunobu反应和亲核加成反应的两步反应制得,其结构经1H NMR和13C NMR表征。  相似文献   

2.
锌粉还原法制备2-氟-5-硝基苯胺   总被引:1,自引:0,他引:1  
在乙醇和水的混合介质中,利用锌粉还原2,4-二硝基氟苯制备2-氟-5硝基苯胺。其制备2-氟-5硝基苯胺的适宜条件:在50~60℃下回流,2,4-二硝基氟苯与锌粉的摩尔比为1:4,混合试剂中乙醇和水的体积比为3:2,收率达70.1%。  相似文献   

3.
氰氟草酯的合成   总被引:2,自引:0,他引:2  
以(S)-乳酸甲酯为原料,与对甲苯磺酰氯反应制备(S)-对甲苯磺酰乳酸甲酯,再与对苯二酚反应制备(R)-2-(4-羟基苯氧基)丙酸乙酯,然后与3,4-二氟苯腈反应制备(R)-2-[4-(4-氰基-2-氟苯氧基)苯氧基]丙酸乙酯,经水解、酯化合成氰氟草酯,总收率49%,化学纯度95%,光学纯度98%。  相似文献   

4.
以2,4’-二氟二苯酮和锍盐(CH3)3SHSO4为原料,在碱性条件下反应生成1-(2-氟苯基)-1-(4-氟苯基)环氧乙烷。通过正交实验确定最佳工艺条件为:氢氧化钾、甲醇和2,4’-二氟二苯酮的物质的量比为6∶1.25∶1,反应温度45℃。以2,4’-二氟二苯酮计,产品收率为91.23%,含量为97.45%。  相似文献   

5.
氟苯水杨酸     
氟苯水杨酸副作用小、强效、低毒,是阿司匹林很好的替代产品。公认的可工业化的生产方法是以2,4-二氟苯胺为原料,经偶联、酰化、水解、羧化等一系列反应制备。氟苯水杨酸已经在欧美、日本等70多个国家得到了广泛应用,年销售额超过1亿美元;我国浙江大学和巨化集团都对氟苯水杨酸进行了研究和开发工作,但国内尚没有工业化生产。制约氟苯水杨酸推广应用的主要原因是价格昂贵,这有赖于生产技术进步来解决。  相似文献   

6.
本文研究了治疗骨髓增殖性肿瘤药物TG101209的合成工艺。以2,4-二羟基-5-甲基嘧啶为起始原料,与三氯氧磷、氨水发生氯化、取代反应生成2-氯-4-氨基-5-甲基嘧啶(B),B再与N-叔丁基-3-溴苯磺酰胺(C)发生Buchwald偶联反应得到3-[(2-氯-5-甲基-4-嘧啶基)胺基]-N-(叔丁基)苯磺酰胺(D)。以甲醇为溶剂,D与CH3OH-HCl反应得到3-[(2-氯-5-甲基-4-嘧啶基)胺基]-N-(叔丁基)苯磺酰胺盐酸盐(E),E与1-甲基-4-(4-氨基苯基)哌啶(G)发生亲核取代反应得到N-叔丁基-3-(5-甲基-2-[4-(4-甲基-1-哌嗪)苯胺基]-4-胺基嘧啶)-苯磺酰胺(TG101209)。总收率达到30.9%,HPLC测得纯度达到99.7%。  相似文献   

7.
以2,4-二氟硝基苯、溴代乙酸乙酯和丙炔溴等为原料,经取代、醚化、还原关环、硝化、N-烷基化、再还原后得中间体7-氟-6-胺基-2H-1,4-苯并嗯嗪-3(4H)-酮,在醋酸溶剂中与3,4,5,6-四氢苯酐反应得到目的产物丙炔氟草胺。经IR和1H—NMR测定,产品结构与丙炔氟草胺一致。总收率28%。  相似文献   

8.
2,4-二硝基二苯胺的微波合成实验研究   总被引:1,自引:0,他引:1  
张玮 《河北化工》2009,32(6):20-21
采用微波加热方法,以2,4-二硝基氟苯为原料合成了2,4-二硝基二苯胺。该反应操作方便,反应速度比常规加热快38倍,反应总收率可达90.5%。合成的目标化合物通过红外光谱和熔点测定分析对其结构进行确证。  相似文献   

9.
以2,6-二硝基-4-三氟甲基氯苯为起始原料,与氨水反应生成2,6-二硝基-4-三氟甲基苯胺;该苯胺与乙酰硝酸酯反应生成N-硝基-2,6-二硝基-4-三氟甲基苯胺;以三乙胺为缚酸剂,N-硝基-2,6-二硝基-4-三氟甲基苯胺与固体光气在二氯甲烷中反应,生成酰氯中间体;酰氯中间体再与取代苯胺反应得到了7种含N-硝基的不对称脲类化合物。产物经IR1、HNMR、质谱、元素分析表征。对目标化合物进行了除草生物活性测试,初步测试结果表明:当其水溶液质量浓度为500 mg/L时,脲基另一端的苯环为2-氯苯基、4-氯苯基、2-甲基苯基、4-甲基苯基时,这些化合物对稗草的校正根长抑制率和校正茎长抑制率都大于40%;但这些化合物对苋菜作用不明显,对苋菜的校正根长抑制率和校正茎长抑制率小于20%。  相似文献   

10.
氟苯水杨酸的合成   总被引:1,自引:0,他引:1  
张奎  许文松 《浙江化工》2004,35(2):4-5,44
以2,4-二氟苯胺为原料,经重氮化、Gomberg-Bachmann偶联、Friedel-Crafts酰基化、Baeyer-Villiger氧化、水解及Kolbe-Schmitt羧化制得氟苯水杨酸,单程收率达到67.6%.  相似文献   

11.
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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