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1.
唑来膦酸钠的合成工艺改进   总被引:2,自引:0,他引:2  
在绿色环保离子液体介质中以咪唑-1-基乙酸盐酸盐为原料,通过与磷酸和三氯化磷缩合、水解制得唑来膦酸,再与氢氧化钠反应、成盐得标题化合物.总收率50%.此工艺反应条件温和、原料易得、操作简便、产率高、环境友好、产品纯度高,既适应于工业化生产,又使成本显著降低,且反应介质离子液体可方便回收并重复利用.  相似文献   

2.
在绿色溶剂离子液体介质中,以3-甲基-4-硝基苯甲酸为起始原料,合成了新药替米沙坦.结果合成了新药替米沙坦,总产率65.8%.该方法反应条件温和,操作简便,产率高,环境友好,且反应介质离子液体可方便回收并重复利用.  相似文献   

3.
离子液体中酯化反应的研究进展   总被引:1,自引:1,他引:0  
离子液体被誉为"绿色"介质,由于具备液程宽、良好的热稳定和化学稳定性,与许多小分子物质杰出的相溶性、高的极性和导电性、再循环能力强和可忽略的蒸气压等众多优良性质,被广泛应用在酯化反应中.对以离子液体作为反应介质时进行的酶催化酯化反应、纤维素改性、生物柴油转化等反应的研究进展进行了介绍.  相似文献   

4.
刘海燕  丁伟  曲广淼  于涛 《化学试剂》2008,30(2):92-94,108
采用未经改装的家用微波炉,在无溶剂的状态下以N-甲基咪唑(mim)为原料合成了系列卤化1-烷基-3-甲基咪唑离子液体,考察了微波功率、加热时间、加热方式、原料的物料比对产品收率的影响.用傅里叶红外光谱仪表征其结构,用沉淀滴定法测定了系列卤化1-烷基-3-甲基咪唑离子液体的相对分子质量.用微波辅助合成咪唑离子液体的方法无需密闭反应容器,避免使用有机溶剂作为反应介质,大大地缩短了反应时间,是实验室制备离子液体实用、有效的方法.  相似文献   

5.
在乙腈介质中,由酸性离子液体和ZnCl2组成的催化体系,可以高效地实现对环己酮肟液相Beckmann重排制己内酰胺的反应.反应过程中生成的唯一副产物环己酮,可以通过氨氧化反应生成原料环己酮肟.考察了溶剂种类、反应温度、反应时间、离子液体用量和ZnCl2用量对环己酮肟重排反应性能的影响.确定了适宜的反应条件;HSO3-b...  相似文献   

6.
主要介绍1-丁基-3-甲基咪唑氟硼酸盐离子液体作为反应溶剂,用于Phosphor-aldol反应.与有机溶剂作介质的反应条件相比,离子液体中的反应条件相对温和,一般情况下反应可在常温、常压下进行,在反应速率、转化率和选择性上与有机溶剂相近.同时,离子液体能循环利用,节约了资源,倡导了绿色化学的理念.  相似文献   

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离子液体由于具有特殊的性质,包括挥发性低、极性大、良好的热稳定性、通过调整阴阳离子选择不同的溶解性等特点,已经作为反应介质或催化剂广泛应用于有机合成领域,引起了人们足够的兴趣.与传统有机溶剂反应相比,离子液体相反应得到的产物收率高,选择性好,加快部分类型反应的速率,后处理简单以及离子液体催化剂体系简单,回收后,可多次重复使用.本文综述了离子液体作为反应介质或催化剂在有机合成传统反应类型中的最新研究成果,主要包括:氧化还原反应、Beckmann重排反应、偶联反应、Diels- Alder反应、氢甲酰化反应、Knoevenagel缩合、烷基化及Blanc氯甲基化反应.  相似文献   

8.
采用在多种1,3-二烷基咪唑和烷基吡啶等离子液体中催化合成丙酸苄酯,研究离子液体种类、原料配比、反应时间、反应温度、催化剂用量等对产率的影响。结果显示:选用[C2Mim]BF4离子液体为反应介质,TBAC(四丁基氯化铵)为催化剂,较佳工艺条件为n(丙酸钠):n(氯化苄)=1.3∶1,75℃下反应2.5 h,TBAC的用量0.62 g,产率可达到97.4%。反应结束后可以通过简单的倾析使产品与离子液体分离,离子液体可以重复使用多次。  相似文献   

9.
以三氯化铝、吡啶和HCl为基本原料,合成出一种离子液体,并在高压釜中考察了这种离子液体对异丁烷与丁烯烷基化反应的催化效果以及相关反应条什的影响.实验结果表明,所合成的离子液体对异丁烷与丁烯的烷基化反应具有较好的催化性能,在催化反应过程中,离子液体可重复使用,稳定性较好;失活后的离子液体可以用AlCl3进行再生:而且,离子液体与烷基化产物很容易分离.  相似文献   

10.
离子液体中芳香醛选择性还原胺化反应研究   总被引:3,自引:0,他引:3  
以离子液体为反应介质,对一系列还原胺化反应进行了研究.结果表明,经过缩合、还原两步连续反应,芳香醛与胺的产品收率在70%~98%,还原剂硼氢化钠在BMImBF4离子液体中对还原胺化反应表现出很好的还原能力和选择性,该合成反应条件温和,离子液体可稳定重复使用12次以上.  相似文献   

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Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.  相似文献   

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2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
收集了2008年7月~2009年6月世界塑料工业的相关资料,介绍了2008~2009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、环氧树脂、不饱和聚酯树脂)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   

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   

17.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  相似文献   

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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