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1.
本文报道1,2-(2′-对甲苯磺酰基乙氧基)-苯的合成改进,改进后反应条件温和,产物容易处理,收率较好。  相似文献   

2.
利越  陈京才等 《化学试剂》2001,23(3):137-138,165
通过4,5-二硫基-1,3-二硫杂环戊烯-2-硫酮(DMIT)的钠盐与2,3-二溴-1,4-丁二醇的反应成功的合成了题目化合物。比较了DMIT钠盐与DMIT锌配合物(DMIT)2Zn(NBu4)2的亲核反应能力,讨论了反应时间、反应温度、碱的用量等条件对反应的影响。并用IR、^1HNMR、MS对目标化合物进行了表征。  相似文献   

3.
对阻燃剂2,2-二(氯甲基)-1,3-亚丙基-四(2-氯乙基)二磷酸酯(简称P-CEP)的合成进行了研究,以季戊本醇和三氯化磷为起始原料,通过闭环,开环和缩合反应合成目标化合物。  相似文献   

4.
本文研究了反式,反式-1,4-二苯基-1,3-丁二烯(DPB)在沸石NaZSM-5中的光敏氧化反应,在溶液中9,10-二氰基蒽(DCA)敏化光氧化反应有两种机制:单重态氧机制和电子转移产生超氧负离子机制,我们把DPB吸附在沸石ZSM-5孔道中,DCA溶解于沸石外部溶剂季戊四醇三甲醚中,溶剂和敏化剂都不能进入沸石孔道,光照反应后,在沸石孔道中只得到DPB的单重态氧的反应产物,没有电子转移的产物产生,  相似文献   

5.
张金艳  叶非 《精细化工》2002,19(8):493-495
以w(NaOH)=33%水溶液为催化剂、乙醇胺、丁酮和二氯乙酰氯为原料,一步法合成了3-二氯乙酰基-2-甲基-2-乙基-1,3-恶唑烷。采用正交实验设计获得最佳反应条件;三氯甲烷做溶剂,反应温度-4-4℃,反应搅拌时间1h,产物收率78.6%。产品经红外光谱、核磁共振和元素分析确证。  相似文献   

6.
以乙酸乙烯酯为原料,经氯化、水解与硫脲环合反应制备2-氨基噻唑,收率91%。将其在硫酸体系中,经成盐-硝化“一锅法”合成2-氨基-5-硝基噻唑。当反应物n(2-氨基噻唑):n(硫酸):n(硝酸)=1:4:1.05,30℃反应4小时,硝化产物收率为81%。  相似文献   

7.
李再峰  罗富英 《化学世界》2001,42(4):194-195,180
首先以间二氯苯、氯乙酰氯、咪唑为原料合成E-2′-(1-咪唑基)-2,4-二氯乙酮肟(I)和以氯苯或溴苯合成对氯(对溴)-α-氯乙苯(ⅡA和ⅡB),Ⅰ分别与ⅡA和ⅡB反应,生成E-2′-(1-咪唑基)-o-(α-甲基对卤苄基)-2,4-二氯苯乙酮肟硝酸盐二个新化合物,产率为60.0%和56.0%,二者的结构经元素分析、IR和^1HNMR表征。  相似文献   

8.
孔祥文  张静 《染料工业》2001,38(5):26-27
以1,8-二氨基萘和丙酮为原料,无水乙醇为溶剂,对甲苯磺酸催化下合成了2,2-二甲基2-,3-二氢Bai啶,适宜的反应条件为:原料摩尔比(1,8-二氨基萘/丙酮)1:15对甲苯磺酸用量1%(以1,8-二氨基萘计),反应时间1.0小时,反应温度为55-60℃,收率为84.0%,UV,IR,1HMR符合结构特征,滤液循环套用后,产品收率由84.0%提高到92.9%,套用4次时,产品质量基本稳定。  相似文献   

9.
董兆恒  郭静等 《精细化工》2002,19(7):398-399,402
对5-烷基-2-(4-氰基苯基)-1,3-二恶烷的合成进行了研究,以5-烷基-2-(4-氰基苯基)-1,3-二恶烷的合成为例,论述了以溴代烷和丙二酸二乙酯为初始原料,采用相转移催化烃基化反应合成了2-戊基丙二酸二乙酯,收率91.7%;进而以四氢铝锂和硼氢化钠为还原剂于0-20℃在四氢呋喃溶剂中合成了2-戊基丙二醇,收率≥80%;再与对氰莽本甲醛在催化剂氯化钙存在下反应全盛了5-烷基-2-(4-氰基苯基)-1,3-二恶烷,收率≥90%,并通过核磁共振氢谱和红外光谱证实了其结构。  相似文献   

10.
2—噻吩乙胺的合成   总被引:2,自引:0,他引:2  
李寿芬 《广西化工》2001,30(2):15-16
以噻吩为起始原料,经过Vilsmeier反应,Darzens反应和Leuckart反应得到2-噻吩乙胺,总收率为52.4%,本合成线路对传统的合成方法进行了改进,简化了反应步骤,所用原料易得,价廉,是工业化生产值重探索的途径。  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   

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14.
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   

15.
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   

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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