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1.
光气法合成3,4—二氯苯基异氰酸酯   总被引:2,自引:0,他引:2  
由光气与3 ,4 -二氯苯胺合成3,4 -二氯苯基异氰酸酯 ,收率≥90%。  相似文献   

2.
3,4-二氯苯基异氰酸酯(DCPI)是一种重要的化工原料,主要用于脲类除草剂、杀虫剂等农药的合成和一些医药中间体的合成。DCPI的生产方法是在惰性溶剂的作用下,利用3,4-二氯苯胺(DCPA)与光气作为原料,经过光化和精馏2个阶段生产DCPI的。国内对DCPI的生产目前主要采用间歇法,该法存在反应时间长、原料DCPA和光气的收率都较低等缺点。  相似文献   

3.
刘琦  朱明华 《江苏化工》2006,34(6):12-13
由3,4-二氯硝基苯制备3-氯-4-氟硝基苯是氟氯苯胺制备中的重要一步,研究了影响氟化反应收率的因素,并确定了合理的工艺条件为:n(KF)∶n(3,4-二氯硝基苯)=1.8~2∶1,反应温度为185~190℃,反应时间1~1.2h,产物3-氯-4-氟硝基苯收率达83%以上。  相似文献   

4.
以固体光气代替光气与3,4-二甲氧基苯胺(藜芦胺)反应合成3,4-二甲氧基苯异氰酸酯,分析了影响反应的各种因素,优化后的合成条件为:以氯仿为溶剂,n(固体光气)∶n(藜芦胺)=1∶2,滴液温度0~5℃,回流温度62℃,保温时间6h。此条件下合成的产品纯度99.3%,收率82.1%。与光气法相比,该法安全方便,产品纯度和收率高。产品用红外光谱、核磁共振仪、气质联用仪进行了表征。  相似文献   

5.
3,4-亚甲二氧基苯乙胺的合成新方法   总被引:1,自引:0,他引:1  
以胡椒胺为原料,通过Sandmeyer反应制得3,4-亚甲二氧基溴苯(收率75.0%),再经Grignard反应(收率74.8%)、酯化反应(收率94.0%)和Gabriel反应(收率63.0%)制备出3,4-亚甲二氧基苯乙胺,并通过红外光谱和色谱-质谱联用确定了目标产物的结构。讨论温度对各步反应的影响,确定了最佳反应条件。  相似文献   

6.
以3,4-二氯苯胺和对氯苯异氰酸酯反应制备N-(4-氯苯基)-N’—(3,4-二氯苯基)脲,以甲苯为溶剂,在回流状态下反应2小时,反应完毕,冷却到0-5℃,过滤,洗涤,重结晶得白色针状结晶,收率可达95.0%以上。  相似文献   

7.
张勇 《安徽化工》2012,38(5):38-39
以3,4-二氯苯腈为起始原料,通过分步氟化,实现了高收率制备3,4-二氟苯腈的方法。相比于先前的报道,本工艺不仅收率提高,同时有效地控制了体系焦化、聚合、变黑等高温下不利因素的影响。  相似文献   

8.
盐酸埃罗替尼是第一个应用于临床的口服表皮生长因子受体(EGFR)抑制剂,其中3,4-二(2-甲氧基乙氧基)苯腈是盐酸埃罗替尼合成的关键中间体。以儿茶酚为原料,经醚化、Vilsmeier反应、氰基化3步反应合成了3,4-二(2-甲氧基乙氧基)苯腈,总收率达61.2%,产品结构经NMR和MS确证。该工艺原料价廉易得、操作简便、成本较低、收率较高,适合工业化生产。  相似文献   

9.
以丙烯酸(AA)和双环戊二烯(DCPD)为主要原料,合成了丙烯酸双环戊二烯酯(DCPA)。采用单因素试验法探讨了催化剂含量、单体配比、反应温度和反应时间等对DCPA收率的影响,从中优选出合成DCPA的最佳工艺条件。结果表明:以磷钨酸为催化剂,并且当反应温度为70℃、反应时间为10 h、n(AA)∶n(DCPD)=1.2∶1和w(磷钨酸)=2.0%时,DCPA的收率(52.41%)相对最高。  相似文献   

10.
光气路线合成4-氯丁酰氯   总被引:2,自引:1,他引:2  
介绍了以γ -丁内酯为原料 ,通过光气化反应制备 4 -氯丁酰氯的方法 ,对主要的影响作了考察 ,优惠工艺条件 :光化反应温度 135℃ ,反应时间 10h ,γ -丁内酯与光气的配比为 1∶1 1(mol/mol) ,催化剂用量 5 %,反应收率 95 %。  相似文献   

11.
提出一种合成对氟、3,5-二氟(氯)苯膦酸酯的有效方法。通过对氟溴苯、3,5-二氟溴苯(均三氯苯)与亚磷酸三甲酯在光照下反应,得到相应的苯膦酸酯。对合成的苯膦酸酯进行了质谱和核磁(1H NMR)表征,并考察了反应条件(反应物投料比、反应温度、反应时间)对转化率的影响。研究发现,与均三氯苯为原料相比,含氟溴苯具有更高的选择性(氟不参与反应),在一定反应下,可以得到中等的3,5-二氟苯膦酸酯转化率(42.5%)和收率(33.6%)。得到的对氟、3,5-二氟苯膦酸酯很容易从产物中分离。此外,在相同反应条件下,以对氟溴苯、3,5-二氟溴苯、或者均三氯苯为原料,转化率基本相同。  相似文献   

12.
邻二氯苯和丁二酸酐经付-克酰化制得,再经还原、付-克酰化和闭环等反应得到抗抑郁剂舍曲林的中间体4-(3,4-二氯苯基)-3,4-二氢-1(2H)-萘酮,总收率50%。第1步反应n(AlCl3):n(丁二酸酐)=2.2:1较为适宜。  相似文献   

13.
2, 4 二氯苯乙酮经溴化得ω 溴 2, 4 二氯苯乙酮,该化合物与丙三醇反应并脱水得 2 (2, 4 二氯苯基 ) 2 溴甲基 4 羟甲基 1, 3 二氧戊环,再在常温下与苯甲酰氯反应合成 2 (2, 4 二氯苯基) 2 溴甲基 4 苯甲酰氧基甲基 1, 3 二氧戊环,然后在 130℃与 1H 1, 2, 4 三唑钠反应 36h,所得产物经水解得 1 [2 (2, 4 二氯苯基 ) 4 羟甲基 1, 3 二氧戊环 2 基]甲基 1H 1, 2, 4 三氮唑,再在室温以吡啶作缚酸剂,与甲磺酰氯反应 20h,合成 1 [2 (2, 4 二氯苯基) 4 甲磺酰氧基甲基 1, 3 二氧戊环 2 基]甲基 1H 1, 2, 4 三氮唑,最后与各类羧酸的钾盐反应,合成了 10种 1 [2 (2, 4 二氯苯基 ) 4 酰氧基甲基 1, 3 二氧戊环 2 基 ]甲基 1H 1, 2, 4 三氮唑类化合物。产物的结构经GC MS、IR证实。对目标产物进行了杀菌活性测定,结果表明,各化合物均具有不同程度的生物活性,其中: 1 [2 (2, 4 二氯苯基) 4 (α 甲基苯乙酰氧基)甲基 1, 3 二氧戊环 2 基]甲基 1H 1, 2, 4 三氮唑对水稻稻瘟病菌和油菜菌核病菌的抑制率,分别达到 92 1%与 95 6%,对小麦赤霉病菌和瓜类灰霉病菌的抑制率达到 80%以上;1 [2 (2, 4 二氯苯基) 4 对氟苯甲酰氧基甲基 1, 3 二氧戊环 2 基 ]甲基 1H 1, 2, 4 三氮唑对水稻稻瘟病菌和油菜菌核病菌的抑制率分别为 9  相似文献   

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15.
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   

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   

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18.
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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