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1.
A series of potassium-doped MgO catalysts loaded with KOH up to 15 mol% was prepared and evaluated for a single step synthesis of propionitrile from acetonitrile methylation with methanol. As the amount of potassium dope increased, both the acetonitrile conversion and the selectivity toward propionitrile increased. Based on the activity data coupled with CO2-TPD and NH3-IR ones, it was concluded that potassium doping to MgO resulted in the enhancement of both basicity and bifunctionality — methylation and hydrogenation.  相似文献   
2.
The enthalpies of mixing of some n-nitriles (from acetonitrile to valeronitrile) aqueous solutions with dodecyltzimethylammonium bromide, sodium dodecylsulfate and dodecyltzimethylammonium oxide micellar solutions were determined. The measurements were performed by systematically changing the surfactant concentration at a given solute concentration. The experimental enthalpies were rationalized in terms of the standard enthalpy of transfer of solute from the aqueous to the micellar phase and of the distribution constant between the two phase. Information on the effect of the nature of the surfactant on the standard thermodynamic quantities of transfer(G t o , H t o , TS t o ) is reported. The present data are compared to those previously reported for primary alcohols and the solubilizing properties shown by the different types of micelles are discussed.  相似文献   
3.
采用平衡法测定了丙烯腈+水、己二腈+水、丙腈+水三个二元体系在不同温度(303.15、313.15、323.15、333.15K)下的液-液相平衡数据;并采用NRTL(α=0.2,α=0.3)模型和UNIQUAC模型对液-液平衡数据进行了关联.结果显示,NRTL和UNIQUAC模型对三个二元体系在不同温度下的互溶度关联的目标函数值均小于1×10-17,实验值与计算值吻合较好,绝对偏差小于0.009,关联精度较高.该研究结果可为丙烯腈、丙腈和水三元平衡溶解度数据的模拟和预测提供可靠的基础数据,并对电解二聚法生产己二腈中电解液的分离提纯工艺具有一定的指导意义.  相似文献   
4.
Excess molar volumes, VmE, have been obtained as a function of composition for ternary-pseudobinary mixtures of [(benzene + cyclohexane or methylcyclohexane) + (propionitrile + cyclohexane or methylcyclohexane)] from the densities measured by means of a vibrating-tube densimeter at atmospheric pressure and a temperature of 298.15 K. The values of VmE have been correlated using the Redlich–Kister equation to estimate the coefficients and standard errors. The experimental and calculated quantities are used to discuss the mixing behavior of the components. The results show that the third component, cyclohexane or methylcyclohexane, has a significant effect on the interaction between benzene and propionitrile.  相似文献   
5.
报道了3种含双官能团苯基醚化合物2-(2,6-二氯苯氧基)丙腈,N-羟基-4-丁基苯乙酰胺,2-(1-甲基乙氧基)苯酚甲氨基酸甲酸酯的电子轰击质谱破裂,用亚稳分析和低能碰撞诱导解离子研究了3种化合物的分子离子碎裂规律,除简单的直接键断裂外,还证实经历了离子/中性(碎片)复合物中间体的单分子解离反应同时存在的竞争机理,解释了观察到分子内单氢迁移,双氢迁移现象。  相似文献   
6.
This work deals with the phase transfer catalysed cyanide displacement reaction on 1-(4-isobutyl phenyl) ethyl chloride to synthesize 2-(4-isobutyl phenyl) propionitrile, which is an intermediate for the synthesis of ibuprofen analogs, belonging to a class of NSAID (nonsteroidal anti-inflammatory drugs). The reaction was studied using solid–liquid phase transfer catalysis (S-L PTC) with trace quantities of water, forming the so-called omega phase at 90 °C. The rates of reaction and selectivity to the product are enhanced in the S-L(org.)-L (ω) PTC in comparison with S-L PTC, which in turn is superior to L-L PTC; the latter suffers from the disadvantage of side reactions in the aqueous phase. In the current work, the effects of various parameters such as catalyst structure, catalyst loading, substrate loading and temperature were studied on the conversion and rates of reaction of 1-(4-isobutyl phenyl) ethyl chloride with solid sodium cyanide under S-L and S-L(ω)-L PTC at 90 °C with toluene as the organic solvent. Tetrabutylammonium bromide (TBAB) was found to be the best catalyst. The role of omega liquid phase in intensification of the S-L PTC was theoretically and experimentally investigated. The kinetic constants have been determined and the apparent activation energy is found as 4.2 kcal/mol, which suggests that the reaction is quite fast, which is likely to bring in mass transfer effects.  相似文献   
7.
The excess molar volumes VEm for ternary pseudo-binary mixtures of [(benzene+chloroform or carbon tetrachloride)+(propionitrile+chloroform or carbon tetrachloride)] have been determined over the full composition range, by measuring the densities with a vibrating-tube densimeter at 298.15 K and atmospheric pressure. The experimental and calculated quantities are compared to those for the binary mixture (benzene+propionitrile), and the mixing behavior of the components is discussed. The results show that adding the third component, chloroform or carbon tetrachloride, to the binary mixture has a small effect on the interaction between benzene and propionitrile.  相似文献   
8.
<正> 芳香卤代物芳环上的卤原子在光诱导或电引发下可通过自由基链式亲核取代反应(S_(RN)|)而被有机负离子所取代。 我们以3-溴苯基-苯基-甲酮为底物,在丙腈碳负离子存在下进行光照,结果芳酮环上的溴原子未发生 S_(RN)|取代,而是在羰基上发生了光诱导加成反应,生成了未见文献报道的新化合物1-苯基-1-(3-溴苯基)-2-氰基丙醇-1(I)  相似文献   
9.
李宁  宗敏华  王菊芳  刘晨  吴虹 《中国化学》2003,21(10):1360-1363
IntroductionOverthepastyears ,thesynthesisofchiralaldehyde cyanohydrinswaswellstudied .1Incontrasttochiralalde hyde cyanohydrins ,therewereonlyfewreportsaboutthepreparationofopticallyactiveketone cyanohydrins ,2 whichareusefulstartingmaterialsandintermediatesforthesyn thesisofmanychiralnaturalproducts .3Wethereforefo cusedonthepreparationofopticallyactivesiliconcontain ing (R ) ketone cyanohydrin ((R ) 2 trimethylsilyl 2 hy droxyl propionitrile)usingacetonecyanohydrinastran scyanationagen…  相似文献   
10.
Summary The asymmetric hydrogenation of ethyl 2-acetoxyacrylate (EtA) by cinchonidine modified Pd/Al2O3 and Pt/Al2O3 catalyst is described (ee up to 60 &percnt;). This is the first example of asymmetric hydrogenation of an enol esters in heterogenized conditions.  相似文献   
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