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441.
The general kinetics of the addition of benzyl bromide to trimethylvinylsilane in the presence of the Fe(CO)5—DMF system has been studied. The reaction orders with respect to each reagent found in the study correspond to a radical chain mechanism of the process. The metal-complex system takes part only in the initiation stage and only at a strictly defined ratio of the components.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1418–1422, August, 1993. 相似文献
442.
1 INTRODUCTION 2-Hydroxyl-4-methoxyacetophenone, paeonol, is the effective component of many traditional Chinese medi- cines. It is proved that in modern medicine paeonol has various effects including antibacteria, antiinflammation, relieving pain, antisensitive and strengthing immune sys- tem[1~3]. The ramifications of paeonol have attracted con- siderable attention also because of their potential bio- logical properties and catalytic activity[4~6]. Recently, a few new derivatives of pae… 相似文献
443.
M. G. Levkovich N. D. Abdullaev R. F. Ambartsumova 《Chemistry of Heterocyclic Compounds》2002,38(5):612-615
We have studied the 13C NMR spectra of 2-phenyl- and 2-benzyliminohexahydro-1,3-thiazepines, and also their alkyl, acyl, carbamoyl, and thiocarbamoyl derivatives. We have shown that introducing substiuents both into the 2 position and into the 3 position of the thiazepine ring mainly affects the chemical shifts for the C(4) of the heterocycle. 相似文献
444.
R. A. Gadzhili A. G. Aliev R. A. Nadzhafova R. I. Ibragimov 《Chemistry of Heterocyclic Compounds》2005,41(8):1009-1012
The reaction of 3-chloro-2-halo-1-propenyl ketones with β-aminocrotonic acid ethyl ester leads to the formation of ethyl esters
of 6-alkyl(aryl, benzyl, cyclohexyl)-4-chloromethyl-2-methylnicotinic acids. It was established that at increased temperatures
the compounds obtained are partially converted into the corresponding dihydrofuro[3,4-c]pyridines.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1184–1188, August, 2005. 相似文献
445.
446.
用皮考林酰胺、六水合硝酸钴和苄基溴反应制得一种新配合物[(C6H6N2O)2Co(H2O)2].B r2,通过红外光谱、元素分析及X射线晶体衍射对化合物进行了表征.结构分析结果表明,配合物属单斜晶系,P2(1)/n空间群,晶胞参数为:a=0.647 61(5)nm,b=1.026 43(9)nm,c=1.264 14(11)nm,β=93.823 0(10),°V=0.838 44(12)nm3,Z=4,Dc=1.977 g/cm3,μ=5.812 mm-1,F(000)=490,R1=0.071 0,wR2=0.251 6.配合物中,Co(Ⅱ)离子为六配位的八面体构型;相邻单元间通过N—H…B r和O—H…B r氢键相互连结而形成三维网状结构. 相似文献
447.
448.
Cornstarch derivative (ES), prepared using diethyl sulfate as an etherifying reagent, was blended with castor oil-based polyurethane (PU) prepolymer to obtain a series of semi-interpenetrating polymer network (semi-IPN) materials, named as UES films. Simultaneously, other kinds of semi-IPN (UBS2) were prepared from PU and benzyl starch (BS2) to compare the effects of the substitute groups. The differences in the miscibility and properties of the two series of materials were investigated using attenuated total reflection Fourier transform infrared spectroscopy, atomic force microscopy, dynamic mechanical thermal analysis, ultraviolet-visible spectroscopy, water-sensitivity and tensile testing. The experimental results revealed that UBS2 films exhibit stronger interfacial attraction and better phase mixing than the UES films, as a result of specific interactions between the PU hard segments and BS2 phenyl groups. The optical transmittance, water-resistivity, tensile strength, and elongation at break of the UBS2 films were clearly higher than those of the UES films containing the same concentration of PU. In particular, the miscibility and properties of the UES film with 40 wt.-% ES, were very poor, whereas the semi-IPN films containing 70 wt.-% benzyl starch still had a certain miscibility and good properties. Therefore, the phenyl groups play an important role in the improvement of the miscibility and properties of the semi-IPN materials. 相似文献
449.
以K—MnO/F—Al2O3和Cu/SiO2为催化剂,利用固定床串联反应器实现了苯甲酸甲酯连续加氢合成无氯苯甲醇反应过程.K-MnO/y-Al2O3和Cu/SiO2催化剂对于苯甲酸甲酯连续加氢合成苯甲醇具有良好的加氢活性,反应转化率可达89.2%,苯甲醇的选择性为84.1%.在苯甲酸甲酯加氢连续步骤中的氢醛比得到提高,有效地抑制了副产物甲苯的生成.XRD,SEM和TPR表征结果表明:采用吸附沉淀法制备的Cu/SiO2-C15.2催化剂,氧化铜在载体上具有良好的分散性能,并且易于还原,表现出最佳的苯甲醛加氢活性. 相似文献
450.
Queirós Domingues M. S. Rocha Gomes J. I. N. Martins J. A. 《Journal of Thermal Analysis and Calorimetry》2003,74(3):749-759
Dyeing fibers at low temperatures has many advantages such as savings in energy and avoiding alterations to the physical properties
of the fibers being dyed or other fibers also present in blends. The problem of low temperature dyeing in synthetic fibers
is that it difficults the dye diffusion into the fiber. In the case of polyamide 6.6 microfibers, by using benzyl alcohol
as an auxiliary dyeing, it was shown that good diffusion was obtained for the dye exhaustion with metal complex dyes at temperatures
more than 30°C below the normal dyeing temperature for the dye exhaustion with metal complex dyes. Using thermal analysis
methods these results were shown to be caused by the lowering of the T
g of the fiber when in the presence of benzyl alcohol.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献