2-甲氧基-4-丙烯基苯基苄基醚的相转移催化合成研究

在相转移催化剂存在下,以2-甲氧基-4-丙烯基苯酚、氯化苄为原料合成2-甲氧基-4-丙烯基苯基苄基醚,分别研究了反应温度、反应时间、原料配比、催化剂用量等条件对合成反应的影响．确定了最佳工艺条件。该方法合成2-甲氧基-4-丙烯基苯基苄基醚的最佳工艺条件是：反应温度95℃;反应时间2h;n(2-甲氧基-4-丙烯基苯酚)：n(氯化苄)=1：1,05;n(2-甲氧基-4-丙烯基苯酚)：n(氢氧化钾)=1：1．10;催化剂=5．89％(相对于2-甲氧基-4-丙烯基苯酚质量分数),2-甲氧基-4-丙烯基苯基苄基醚的收率可达到92．52％以上,产品纯度98．5％。     

二甘醇二丁醚的制备

采用改进的Ｗｉｌｌａｍｓｏｎ合成反应方法，以二甘醇、溴丁烷及固体氢氧化钠，一步法合成二甘醇二丁醚。就影响醚化反应收率各因素：原料配比、反应温度、反应时间以及催化剂用量进行了探讨，得到最佳的操作条件为：二甘醇：溴丁烷：固碱物质的量比＝１．０：２．２：２．４，反应温度７５℃，反应时间６￣７ｈ，在经条件下收率可达８５％。     

2-溴乙氧基苯的相转移催化合成研究

在四丁基溴化铵相转移催化剂存在下,以苯酚、1,2-二溴乙烷为原料合成2-溴乙氧基苯,分别研究了反应温度、反应时间、原料配比、催化剂用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成2-溴乙氧基苯的最佳工艺条件是:反应温度100°C;反应时间6 h;n(苯酚)∶n(1,2-二溴乙烷)=1∶1.15;n(苯酚)∶n(氢氧化钠)=1∶1.15;溶剂用量为40 mL(相对于0.15 mol苯酚),催化剂用量为1 g(相对于0.15 mol苯酚),2-溴乙氧基苯的收率可达到88.9%以上,产品纯度98.5%。     

微波辐射合成正丁基苯基醚的研究

在微波辐射条件下,以苯酚、氢氧化钾和正溴丁烷为原料,聚乙二醇400为相转移催化剂,无水乙醇为溶剂,合成了正丁基苯基醚.通过测定折射率和红外光谱分析对产物进行了表征.研究了反应物的摩尔比、催化剂与溶剂的用量、微波辐射功率和微波辐射时间等对产物收率的影响.结果表明,当n(苯酚)∶n(氢氧化钾)∶n(正溴丁烷)∶n(PEG-400)=1∶2.0∶3.0∶0.08、乙醇用量为20 mL、微波辐射功率为160 W、辐射时间为4 min时,正丁基苯基醚的收率可达97.58%.     

聚乙二醇催化合成正丁基苯基醚

以乙醇为溶剂、聚乙二醇为相转移催化剂，氢氧化钾为碱，从正丁基溴和苯酚合成了正丁基苯基醚。当0．1mol苯酚，0．3mol正丁基溴，乙醇为溶剂，在氢氧化钾和聚乙二醇400存在下，加热2h正丁基苯基醚收率达96．7％。     

四丁基溴化铵催化对氰基苯酚醚化反应的研究

以对氰基苯酚和1，3-二溴丙烷为原料，四丁基溴化铵为催化剂，制备1，3-二（对氰基苯氧基）丙烷。考察了催化剂的用量、原料配比、温度和时间对收率的影响。优化条件为：n（对氰基苯酚）：n（1，3-二溴丙烷）=2．3：1．0，凡（四丁基溴化铵）：n（对氰基苯酚）=1：12．5，醚化反应温度为50℃，反应时间为8h，1，3-二（对氰基苯氧基）丙烷收率达到71％。避免了有机溶剂的使用及后序处理。     

二甘醇单丁醚的制备

采用改进的Ｗｉｌｌｉａｍｓｏｎ合成反应方法，以二甘醇、氯丁烷及固碱为原料，一步法合成二甘醇单丁醚。就影响醚化反应收率各因素：原料配比、反应温度、反应时间以及催化剂用量进行了探讨，得到最佳的操作条件分别为：ｎ（二甘醇）：ｎ（氯乙烷）＝５．０￣６．０：１．０、反应温度：７０￣１００℃、反应时间：７￣９ｈ、ｎ（氯乙烷）：ｎ（固碱）＝１．０：１．２，在此条件下收率可达８５．５％。     

2-苯基苯并噁唑的合成

以邻氨基苯酚和苯甲酸为原料合成2-苯基苯并噁唑,用正交试验得出最佳合成条件:溴化四丁基铵(TBAB)为相转移催化剂,n(邻氨基苯酚):n(苯甲酸)=1:1.5,反应温度为110℃,反应时间为6h,产率89.5%.     

香料乙酸苄酯的合成

实验以氯化苄、醋酸钠为原料，研究了在相转移催化剂的存在下，一步反应制得乙酸苄酯的合成工艺。结果表明，最佳反应条件为：催化剂用量为n（氯化苄）：n（四丁基溴化铵）=1：1．6×10^-2，反应物为n（氯化苄）：n（乙酸钠）：1：1．05，反应时间是4．5h，反应温度为110℃，收率为92％，产品纯度可达99％。[编者按]     

四正丁基溴化铵催化合成香豆素的研究

以水杨醛和醋酸酐为原料,无水碳酸钾为催化剂来合成香豆素。研究了四正丁基溴化铵的活化作用、四正丁基溴化铵的用量、反应温度以及反应时间对香豆素产率的影响。结果表明：用四正丁基溴化铵作活化剂,香豆素的产率由原来的61.3%提高到84.3%。最佳反应条件：n（水杨醛）∶n（四正丁基溴化铵）=1∶0.04,反应温度160℃,反应时间4h,香豆素的产率可达85.1%。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

基于ATRP法制备的触角状亲水性羟胺树脂的吸硼性能的研究

以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。