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1.
高立方烷-2, 4-二羧酸(1)通过Barton脱羧氯化反应, 可合成出2, 4-二氯高立方烷(3); 而通过改进的Hunsdiecker反应, 则可分别合成出2, 4-二溴高立方烷(4)和2, 4-二碘高立方烷(5)。  相似文献   

2.
7,7,8,8-四氰基对苯醌二甲烷与邻菲咯啉稀土配合物的合成和表征张明杰,聂玉敏,史志勤,张文胜,梁惠来(天津大学化学系天津300072)(天津大学电子工程系天津)关键词四氰基对苯酮二甲烷,邻菲咯啉,镧配合物,钕配合物,合成7,7,8,8-四氰基对苯...  相似文献   

3.
1,3-二叔丁基-5,5-二硝基嘧啶烷(3)是混合炸药含能增塑剂1,3,5,5-四硝基-1,3-二氮杂环环己烷的关键硝化前体.通过研究3的合成反应机理,目的是为制备1,3,5,5-四硝基-1,3-二氮杂环环己烷的工艺优化提供理论依据.以2,2-二硝基-1,3-丙二醇(1)、甲醛和叔丁胺为原料,通过Mannich缩合反应得到1,3-二叔丁基-5,5-二硝基嘧啶烷.采用同位素示踪技术以及分离关键中间体对反应机理进行推测.以氘代甲醛、1和叔丁胺缩合得到氘标记的3,1HNMR和MS分析结果表明:在反应过程中1首先解离生成偕二硝基甲烷和甲醛,小分子碎片随机组合生成了3.分离出了关键中间体1-叔丁氨基-2,2-二硝基乙烷.根据所获得的证据,推断了3的合成反应机理.  相似文献   

4.
随着对高能量密度材料的性能要求不断提高,新型高能量密度材料成为近期研究热点,其中八硝基立方烷(ONC)由于其优越的性能成为其中典型的代表,然而关于八硝基立方烷热分解的动力学机理研究比较少。本文采用ReaxFF反应力场模拟高温条件下凝聚相八硝基立方烷初始热分解过程。研究发现热分解过程中八硝基立方烷笼状骨架结构中C-C键最先发生断裂,并逐步破坏形成八硝基环辛烯等,随后出现NO2和O等,计算结果表明笼状骨架结构的破坏存在三种不同路径。八硝基立方烷在高温条件下热分解的主要产物有NO2、O2、CO2、N2、NO3、NO、CNO以及CO等,其中N2和CO2是终态产物,不同温度对产物均产生不同程度的影响。  相似文献   

5.
六硝基六氮杂异伍兹烷(HNIW)是一笼形硝胺,它是迄今已知的能量最高的高能量密度化合物(HEDC),本文由四乙酰基二甲酰基六氮杂异伍兹烷(TADFIW)合成了HNW。所合成的HNW中含有少量(2%~3%)的未硝解完全的副产物,经分离鉴定,确定其为五硝基一甲酰基六氮杂异伍兹烷(PNMFIW)。以此路线合成HNW有以下优点:催化剂耗量低,反应条件温和,得率高,流程简单等。  相似文献   

6.
本文设计合成了四类端位4-氰基和4-硝基苯甲羧取代的二苯乙炔类化合物,并通过DSC和偏光显微镜对它们的液晶性进行了研究。讨论了二苯乙炔核中全氟亚苯基的左右位置对液晶性的影响,比较了氰基取代和硝基取代的苯甲羧二苯乙炔类化合物的液晶性差异。  相似文献   

7.
鲁东飞  刘尚钟  马影  王敏 《化学通报》2006,69(2):133-135
为了寻求开发新的烟碱类杀虫剂,设计、合成了中间体α_氰基异氰酸酯,然后同2_硝基亚氨基咪唑烷缩合制得6个新咪唑烷衍生化合物。同时从硫脲开始,合成了含α_异丙基对氯苯基的双取代硝基胍。经过初步生物活性测定,所有新化合物具有一定的除草杀虫活性,其中化合物6对马唐的苗后抑制达到61%。  相似文献   

8.
最新的研究发现2-氰基萘(CN)能够发生光二聚反应生成3种类立方烷结构的二聚体,anti-head-to-head 1、anti-head-to-tail 2和syn-head-to-tail 3.本文研究了水溶液中γ-环糊精对2-氰基萘的光二聚反应区域选择性的影响.结果表明,γ-环糊精(γ-CD)能够显著影响2-氰基萘的光二聚反应,在提高反应速率的同时,得到较好的区域选择性,室温下光照CN@γ-CD包结物水溶液,主要得到头-头产物1.  相似文献   

9.
1,3-二叔丁基-5,5-二硝基嘧啶烷(3)是混合炸药含能增塑剂1,3,5,5-四硝基-1,3-二氮杂环环己烷的关键硝化前体. 通过研究3的合成反应机理, 目的是为制备1,3,5,5-四硝基-1,3-二氮杂环环己烷的工艺优化提供理论依据. 以2,2-二硝基-1,3-丙二醇(1)、甲醛和叔丁胺为原料, 通过Mannich缩合反应得到1,3-二叔丁基-5,5-二硝基嘧啶烷. 采用同位素示踪技术以及分离关键中间体对反应机理进行推测. 以氘代甲醛、1和叔丁胺缩合得到氘标记的3, 1H NMR和MS分析结果表明: 在反应过程中1首先解离生成偕二硝基甲烷和甲醛, 小分子碎片随机组合生成了3. 分离出了关键中间体1-叔丁氨基-2,2-二硝基乙烷. 根据所获得的证据, 推断了3的合成反应机理.  相似文献   

10.
建立了由γ-硝基腈合成4,5-二氢吡咯衍生物的新方法.用还原铁粉和浓盐酸混合体系作为还原剂,以甲醇为溶剂,γ-硝基腈在30℃下其硝基被还原成氨基,该氨基与分子内的氰基自发地发生亲核加成反应和重排反应,形成一系列4,5-二氢吡咯杂环化合物.在优化条件下,不同结构的γ-硝基腈均能以满意的收率转变成4,5-二氢吡咯衍生物,说明该反应具有较好的普适性.根据实验结果,提出了可能的反应机理.  相似文献   

11.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

14.
A class of excitable media described by the Fitzhugh-Nagumo equation is investigated. Based on the stable and self adaptive theory, the error between the systems grid variables and the standard sampling of the periodical signal or constant signal was feed back into the system both globally and locally. When the controller was then shut off, automatically, the whole system became homogeneous. Additionally, the scheme was tested under noisy conditions. The numerical simulations results demonstrate its effectiveness. The system reached a homogeneous state and a spiral wave was converted into a target wave, resulting in a wonderful pattern emerging using a different controller. The scheme proved robust in resisting the effects of noise.  相似文献   

15.
AgCuSe nanorods were prepared at room temperature by a redox reaction. The as-prepared product was characterized by X-ray powder diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy.X-ray powder diffraction shows that the as-prepared product is the tetragonal phase of AgCuSe. Transmission electron microscopy shows that the sample consists of nanorods with a diameter varying from 5 nm to 20 nm and a length varying from 200 nm to 600 nm. X-ray photoelectron spectroscopy shows that the purity of the sample is high. The formation mechanism of AgCuSe and the growth mechanism of AgCuSe nanorods were discussed.Thermodynamic calulations show that the final product in the synthetic system is pure AgCuSe. The solvent ethylenediamine did not only acts a didentate ligand to form relatively state Ag + and Cu + complexes, but also dissolved Se and enhanced the reactivity of Se. It played an important role in controlling the nucleation and growth of AgCuSe nanorods.  相似文献   

16.
The lithium-ion-conducting inorganic solid electrolytes in the oxide systems Li2O-SiO2-P2O5 and Li2O-TiO2-SiO2-P2O5 were prepared by the solid-state reaction, and the electrolyte pellet made by cold-pressing method had diameter of 13 mm and was about 1 mm thick. Phase identification and surface morphology of the products were carried out by X-ray diffraction and scanning electron microscopy. Ionic conductivity of the pellets was investigated through ac impedance. The results show that the adding of other cations can improve the ionic conductivity of the solid electrolyte, and the sintering temperature and duration can influence the ionic conductivity. The maximum ionic conductivity in the samples is 9.9 × 10−4 S/cm in the Li2O-TiO2-SiO2-P2O5 system. Original Russian Text ? W. Li, M. Wang, Z.H. Li, X.F. Shang, H. Wang, Y.W. Wang, Y.B. Xu, 2007, published in Elektrokhimiya, 2007, Vol. 43, No. 11, pp. 1341–1345.  相似文献   

17.
以α位(2,4-二特戊基)苯氧基邻苯二腈作为环合前体,制备了多种金属酞菁,产物经元素分析、紫外、红外、核磁氢谱等分析手段进行表征.并选择了部分酞菁进行溴化,其中着重研究了不同中心金属以及溴化对染料Q带吸收的影响.结果表明,酞菁染料的金属化对于其Q带吸收影响很大,多数染料金属化后会出现蓝移,而选择合适的条件进行溴化,可以使得金属酞菁的Q带吸收出现一定程度的红移,其中部分溴化金属酞菁的吸收波长与光信息产业中使用的近红外激光器很接近,具有潜在的实用价值.  相似文献   

18.
Monodisperse crosslinked poly(chloromethylstyrene-co-divinylbenzene) (poly(CMSt-co-DVB)) microspheres were prepared by distillation-precipitation copolymerization of chloromethylstyrene (CMSt) and divinylbenzene (DVB) in neat acetonitrile. The polymer particles had clean surfaces due to the absence of any added stabilizer. The size of the particles ranges from 2.59 μm to 3.19 μm and with mono-dispersity around 1.002-1.014. The effects of monomer feed in copolymerization on the microsphere formation were described. The polymer microspheres were characterized by SEM and chlorinity elemental analysis.  相似文献   

19.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

20.
Viscosity measurements have been made of water-solvent and water-polymer solutions in a temperature range of 20–60 centigrades. A medium structure temperatureT 0 was calculated from the Vogel-equation. Water has a structure temperature of 140–150 K, its decrease indicates structure breakage, an increase structure promotion. Pyridine, dioxane, dimethylformamide and urea are structure breakers. This is explained by a shift of the equilibrium — bonded water molecules — nonbonded — to the right. Acetone shows hydrophobic bonding in the same concentration range of 0–10 mole % as the normal alcohols. They are quasifree liquids-structure temperature zero-in the pure state. This is explained by hydrogen bridged dimer formation with the exception of tert-butanol. Its 3 methylgroups sterically prevent dimer formation and cause structuring. Adding urea to methanol-water solutions breaks water structure according to urea concentration but extends the hydrophobic bonding maximum over the whole diagram. Glucose-water solutions have a minimum in the structure temperature diagram. Its left side indicates waterstructure breakage, its right side formation of a new structure forced upon water by the sugar. The equilibrium can be formulated: Waterlike bonded-nonbonded-hetero (solvent)-like bonded, Ribose also shows this minimum but after a short range of heterobondedness the structure is completely broken to nonbondedness.The polymers dextrane and polyvinylpyrrolidone are strong waterstructure breakers. Dextrane much stronger than PVP, it breaks to nonbondedness while PVP maintains a certain structuring, perhaps indicating heterobonding at higher concentrations. Polyacrylamide is a strong structurebreaker. It resembles urea in this sense. Perhaps the solvationwater structure of the NH2 groups is very different from pure waterstructure. Polyacrylicacid breaks waterstructure completely, if sodiumchloride is added waterstructure is rebuilt again. The only waterstructure promoting polymer is natural gelatine. Perhaps this structure is different from pure water or the watermolecule equilibrium is shifted towards bondedness. The structure temperatures of pure polyethyleneglycoles show a minimum with increasing molecular weight. The high structure temperature of the small chains is explained by long chain assoziates formation through hydrogen bridging. This liquid of long assoziate chains is structured and has a high structure temperature. With increasing molecular weight ringformation instead of linear assoziation becomes possible. These neutral rings form a free liquid. Long chains again have a linear structure and the structure temperature increases at higher molecular weights. Existence of linear chain assoziation of low molecular PEGs is proved with their breakage by adding the chain terminating methanol.Dedicated to Prof. Dr. F. H. Müller.Herrn Chemotechniker D. Ziegler möchte ich für die sorgfältige Durchführung der Messungen sehr danken.Dem Verband der Chemischen Industrie danke ich sehr für die Ermöglichung der Arbeit.  相似文献   

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