FeCl_3/ZnCl_2加压催化酰化制备4-氯二苯甲酮工业化技术

研究了在加压和FeCl3/ZnCl2催化下,4-氯苯甲酰氯和苯发生Friedel-Crafts反应制备4-氯二苯甲酮的工艺。157.6 g苯、88.2 g 4-氯苯甲酰氯和1.3 g FeCl3/ZnCl2混合于1 L的高压釜中,在压力为(0.85～1.1)×106Pa、温度为175～185℃的条件下反应8 h,经纯化处理得到4-氯二甲苯酮93.1 g,摩尔收率为86.2%,w(4-氯二苯甲酮)=99.8%(HPLC)。探讨了压力、催化剂和投料比等对收率的影响。经过一次性投料4-氯苯甲酰氯175 kg的生产型中试验证,4-氯二苯甲酮摩尔收率为82.7%。     

不同氧化剂对Skraup反应合成4-苯基-8-硝基喹啉的研究

以邻硝基苯胺和3-氯苯丙酮为起始原料,采用Skraup反应合成标题化合物.研究了不同氧化剂(FeCl3、ZnCl2、FeCl3/ZnCl2、I2、I2/KI)在不同的温度和不同的时间下,对反应收率的影响,实验表明FeCl3/ZnCl2的联用比单独使用FeCl,或ZnCl2的收率要高;而使用I2/KI为氧化剂的收率最高;...     

降脂药非诺贝特的合成工艺改进

首先,FeCl₃催化苯甲醚和对氯苯甲酰氯发生Friedel-Crafts酰基化反应生成4-氯-4’-甲氧基二苯甲酮(Ⅰ);接着,中间体Ⅰ水解生成4-氯-4’-羟基二苯甲酮(Ⅱ);然后,化合物Ⅱ与丙酮、氯仿缩合得到非诺贝特酸(Ⅲ);最后,中间体Ⅲ与异丙醇酯化生成产物非诺贝特(Ⅳ),进一步纯化后制备非诺贝特晶体。采用MS、FTIR、XRD、¹HNMR和¹³CNMR对产物进行了表征;并用XRD解析了非诺贝特晶体结构。考察了反应条件对中间体及非诺贝特收率的影响。结果表明,合成中间体Ⅰ的优化条件为：n(苯甲醚)∶n(FeCl₃)∶n(对氯苯甲酰氯)=4.0∶0.0125∶1.0,145～155℃反应6 h;合成中间体Ⅲ的优化条件为：n(氯仿)∶n(Ⅱ)=2.5∶1.0,析晶温度为10℃,析晶溶剂为甲苯;合成非诺贝特的优化条件为：n(Ⅲ)∶n(异丙醇)∶n(浓硫酸)=1.0∶3.0∶2.0,用异丙醇精制得到非诺贝特晶体。非诺贝特的总收率可达56.17%(以对氯苯甲酰氯计),产物HPLC纯度达99.93%。     

加压下FeCl_3催化Friedel-Crafts酰化反应合成二苯甲酮

研究了在加压和催化量 Fe Cl3存在的条件下 ,苯甲酰氯和苯发生 Friedel- Crafts酰化反应合成二苯甲酮的工艺。 3 1 5 .2 g苯、1 43 .4g苯甲酰氯和 14.4g Fe Cl3混合于 2 L的高压釜中 ,在压力为 1 .6× 1 0 6～ 1 .8× 1 0 6Pa、温度为 1 80～ 2 0 0°C的条件下反应 8h,经纯化处理得到二甲苯酮 1 49.3 g,收率为 82 .1 %,纯度为 99.8%( GC分析 )     

AlCl3催化合成4-羟基-4摧-氯二苯甲酮

以无水三氯化铝（AlCl3）为催化剂,对氯苯甲酰氯和苯甲醚为起始原料,经过Friedel-Crafts酰基化反应、去甲基反应、水解反应等过程合成了4-羟基-4＆#39;-氯二苯甲酮。考察了催化剂用量、苯甲醚用量、反应温度、反应时间等对产率的影响,得到了较适宜的工艺条件为对氯苯甲酰氯30 g,苯甲醚18 g,三氯化铝33 g,溶剂氯苯80 g,反应温度130℃,回流时间1.5 h,产率97.1％。改进后的方法能节约试剂,节省时间,减少污染。     

AlCl3催化合成4-羟基-4摧-氯二苯甲酮

以无水三氯化铝（AlCl3）为催化剂,对氯苯甲酰氯和苯甲醚为起始原料,经过Friedel-Crafts酰基化反应、去甲基反应、水解反应等过程合成了4-羟基-4'-氯二苯甲酮。考察了催化剂用量、苯甲醚用量、反应温度、反应时间等对产率的影响,得到了较适宜的工艺条件为对氯苯甲酰氯30 g,苯甲醚18 g,三氯化铝33 g,溶剂氯苯80 g,反应温度130℃,回流时间1.5 h,产率97.1％。改进后的方法能节约试剂,节省时间,减少污染。     

4-硝基-4′-氯二苯甲酮的合成研究

对硝基苯甲酰氯和氯苯在无水三氯化铝催化下,生成4-硝基-4′-氯二苯甲酮.通过多因素正交试验,确定最佳工艺条件为对硝基苯甲酰氯:氯苯:无水三氯化铝 = 1.0:2.0:1.3(mol),保温温度70℃,保温时间1.5h.收率为84.33%,含量99.36%.产品结构经红外光谱、核磁共振、质谱和元素分析测定证实.实验操作简单,分离容易.     

4-硝基-4''''-氯二苯甲酮的合成研究

对硝基苯甲酰氯和氯苯在无水三氯化铝催化下,生成4-硝基-4-氯二苯甲酮。通过多因素正交试验,确定最佳工艺条件为对硝基苯甲酰氯:氯苯:无水三氯化铝 = 1.0:2.0:1.3(mol),保温温度70℃,保温时间1.5h。收率为84.33%,含量99.36%。产品结构经红外光谱、核磁共振、质谱和元素分析测定证实。实验操作简单,分离容易。     

4-硝基-4ˊ-氯二苯甲酮的优化合成

研究了4-硝基-4ˊ氯二苯甲酮.以对硝基苯甲酰氯为原料,与氯苯在无水三氯化铝的催化下,经C-酰化反应得到4-硝基-4ˊ-氯二苯甲酮,经过正交试验,得到优化条件为对硝基苯酰氯:氯苯:三氯化铝=1:2.7:1.7(mol),反应时间1.5h,反应温度为70℃,在优化条件下实验的产率为88.9%,纯度99.2%。熔点101-103℃。     

4-硝基-4''''-氯二苯甲酮的优化合成

研究了4-硝基-4'氯二苯甲酮.以对硝基苯甲酰氯为原料,与氯苯在无水三氯化铝的催化下,经C-酰化反应得到4-硝基-4'-氯二苯甲酮,经过正交试验,得到优化条件为对硝基苯酰氯:氯苯:三氯化铝=1:2.7:1.7(mol),反应时间1.5h,反应温度为70℃,在优化条件下实验的产率为88.9%,纯度99.2%.熔点101-103℃.     

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.     

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.     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.