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1.
氯铝酸离子液体催化合成香豆素结构荧光染料   总被引:2,自引:0,他引:2  
以[BMIm]Br-AlCl3离子液体为催化剂,通过4-二乙氨基水杨醛、氰乙酸乙酯和邻氨基苯酚一锅煮反应合成了典型的香豆素结构荧光染料3-(2′-苯并口恶唑基)-7-二乙基氨基-2H-1-苯并吡喃-2-酮。考察了离子液体的催化活性,较系统地研究了催化剂路易斯酸性、催化剂用量、反应温度、反应时间对产率的影响。最佳反应条件为:n(4-二乙氨基水杨醛)∶n(氰乙酸乙酯)∶n(邻氨基苯酚)∶n(离子液体〔n(AlCl3)/n([BMIm]Br-AlCl3)=0.67〕)=1∶1∶1∶1,反应温度100~110℃,反应时间60 min,产物最终实测收率达78.3%。  相似文献   

2.
在正丁醇中,以4-二乙氨基水杨醛与硝基乙酸乙酯为原料,通过Knoevenagel缩合反应合成了3-硝基-7-二乙氨基香豆素,其结构经1H NMR、元素分析及晶体结构表征。研究了该反应的催化剂选择、催化剂用量、原料配比以及助催化剂的用量四个因素对3-硝基-7-二乙氨基香豆素收率的影响,所得最佳合成条件为:催化剂二甲胺摩尔分数为30%,二甲胺与助催化剂冰醋酸1∶1.5 (V∶V),4-二乙氨基水杨醛与硝基乙酸乙酯物质的量的比为1∶3,反应时间12 h, 3-硝基-7-二乙氨基香豆素收率为89.3%。  相似文献   

3.
报道了杀菌剂氟嘧菌酯的合成工艺研究。以4-羟基香豆素为原料,依次经过硝化、碱水解、甲胺化、环合、醚化和碱重排环合反应得到(E)-(5,6-二氢-[1,4,2]-二嗪-3-基)-(2-羟基苯基)-甲酮-O-甲基肟(中间体F);以2-氟丙二酸二乙酯为原料,经与醋酸甲脒成环后进行氯化反应合成中间体4,6-二氯-5-氟嘧啶;中间体F先后与4,6-二氯-5-氟嘧啶和2-氯苯酚进行醚化反应得到目标产物氟嘧菌酯。以4-羟基香豆素计,合成总收率达17%,产品质量分数为96%(HPLC)。  相似文献   

4.
水溶性香豆素衍生物的合成及其光谱性能   总被引:2,自引:0,他引:2  
4-甲氧基水杨醛和丙二酸二乙酯反应合成了中间体7-甲氧基香豆素-3-甲酸,该中间体与二乙醇胺反应合成了水溶性香豆素类衍生物7-甲氧基香豆素-3-甲酰二乙醇胺。用核磁共振(NMR)表征了产物的结构,研究了其紫外吸收光谱和荧光光谱。  相似文献   

5.
祁刚  屠树滋 《精细化工》2007,24(7):714-716
运用拼合原理并根据构效关系研究结果,设计了香豆素噻唑烷二酮类化合物,合成方法是以甲基取代的香豆素为原料,经NBS溴化后,再与5-(4-羟基苄叉)-噻唑烷-2,4-二酮在NaH作用下缩合得到,其中中间体5-(4-羟基苄叉)-噻唑烷-2,4-二酮是由噻唑烷二酮与对羟基苯甲醛在哌啶催化下缩合得到,共合成了5-[4-(香豆素-7-亚甲氧基)苄叉]-噻唑烷-2,4-二酮、5-[4-(4-甲基香豆素-7-亚甲氧基)苄叉]-噻唑烷-2,4-二酮、5-[4-(香豆素-6-亚甲氧基)苄叉]-噻唑烷-2,4-二酮、5-[4-(7-甲氧基香豆素-4-亚甲氧基)苄叉]-噻唑烷-2,4-二酮、5-[4-(3-溴香豆素-7-亚甲氧基)苄叉]-噻唑烷-2,4-二酮、5-[4-(3-溴-4-甲基香豆素-7-亚甲氧基)苄叉]-噻唑烷-2,4-二酮6个香豆素噻唑烷二酮类化合物,结构均经IR1、HNMR、MS确定,两步反应合成目标化合物总产率分别为10.4%、13.1%、7.1%、16.0%、22.0%、18.0%。  相似文献   

6.
以4-(二乙氨基)水杨醛为原料,无水氟化钾为催化剂,通过克脑文格尔反应制备化合物1,并对化合物1的合成条件进行优化,再通过尔斯迈尔-哈克-阿诺德反应和亲核加成-消除反应分别合成化合物2和化合物3[7-(二乙氨基)香豆素衍生物],以化合物3为显色剂,采用微流控纸芯片技术,实现对硫醇类生物标记物同型半胱氨酸(Hcy)、半胱氨酸(Cys)、谷胱甘肽(GSH)含量的特异性分析。结果表明,无水氟化钾可替代哌啶作为催化剂用于合成化合物1,m(无水氟化钾)∶m(反应物)=12%,n[4-(二乙氨基)水杨醛]∶n(乙酰乙酸乙酯)=1∶2,产率可达40.35%;化合物3分别与Cys、Hcy和GSH发生不同显色反应,可以实现对3种生物硫醇的特异性检测。  相似文献   

7.
[目的]改进合成工艺,缩短合成路线,提高总收率。[方法]以4-哌啶腈和氯代乙酰氯为起始原料,经酰胺化反应得到1-(2-氯乙酰)-4-氰基哌啶、然后与3-甲基-5-三氟甲基吡唑和硫化氢气体生成关键中间体1-[2-[5-甲基-3-(三氟甲基)-1H-吡唑-1-基]乙酰基]-4-硫代甲酰胺哌啶;以1,3-二氯丙酮为原料,在氯化氢存在下与亚硝酸叔丁基酯反应生成3-氯-N-羟基-2-氧代-丙胺氯,然后与2,6-二氟苯乙烯环化得到关键中间体2-氯-1-[5-(2,6-二氟苯基)-4,5-二氢异唑-3-基]乙酮。最后2-氯-1-[5-(2,6-二氟苯基)-4,5-二氢异唑-3-基]乙酮与1-[2-[5-甲基-3-(三氟甲基)-1H-吡唑-1-基]乙酰基]-4-硫代甲酰胺哌啶反应得到目标产物氟噻唑吡乙酮。[结果]经1H NMR手段鉴定,产品结构与氟噻唑吡乙酮结构一致,总收率28.4%。[结论]该工艺简单经济,条件温和,适合工业化生产。  相似文献   

8.
赵冰  胡立峰  李志宇  宋波  王丽艳  邓启刚 《化学世界》2012,53(9):547-549,556
在离子液体氯化1-丁基-3-甲基咪唑([bmim]Cl)存在下,Zn粉活化的α-溴代苯乙酮类化合物与6-甲基-4-醛基香豆素发生Reformatsky反应,合成出三种香豆素取代的β-羟基酮类化合物。通过IR和1 H NMR对所合成的化合物进行了结构表征。实验结果表明,离子液体[bmim]Cl能够促进溴代苯乙酮与醛基香豆素的Reformatsky反应,并以较高产率得到香豆素取代的β-羟基酮类化合物。离子液体[bmim]Cl经处理后可循环利用,并且效率较高。  相似文献   

9.
以4-二乙氨基水杨醛、丙二酸环亚异丙酯为原料,经Knoevenagel反应生成7-二乙氨基香豆素-3-羧酸,与氨基酸发生缩合反应后与3-溴丙烯反应,设计合成了3个目标化合物。结构经~1HNMR、~(13)CNMR、ESI-MS等加以表征,并对其荧光性质进行测定。结果表明,3种烯丙端基化合物收率均超过70%,荧光发射峰波长分别为489、498、508 nm,其中7-二乙氨基香豆素-3-酰胺-N-丁酸烯丙酯具有相对较大的Stokes位移,对A549细胞进行染色,绿光激发时,细胞呈现出强烈的绿色荧光,成功实现细胞内荧光成像,具有良好的生物应用前景。  相似文献   

10.
以三聚氯氰(TCT),浓硫酸,对-β-羟基乙砜苯胺硫酸酯和2,4-二羟基二苯甲酮(UV-0)为原料,经三步反应合成一种具有双活性基团的水溶性紫外吸收剂2-{4-[4-(4-苯甲酰基-5-羟基-2-磺酰苯氧基)-6-氯-1,3,5-三嗪-2-酰氨基]苯磺酰基}乙基磺酸钠(UV-SHTES),产物的结构分别用FT IR、NMR、MS、SEMEDS表征。并对反应中各项条件对反应产率的影响进行了探讨。UV-SHTES的最佳合成工艺条件为:n(2,4-二羟基-5-磺酸基二苯甲酮)∶n(双活性基)∶n(Na_2CO_3)=1.1∶1∶1,在水中40℃下反应2h,产率71%。UV-SHTES的紫外吸收性能在240~320nm内表现良好,酸碱稳定性较好,水溶性得到大幅改善。  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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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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