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Capture, rearrangement and/or fragmentation of 1-(5-oxazolyl)-1-alkylidenes and 1-(5-isoxazolyl)-1-alkylidenes are described. 相似文献
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The refrigerant 1-1-1-2-tetrafluoroethane (R134a) is being phased out in Europe from 2011. This requires the adoption of alternatives, and the mixture of R134a with carbon dioxide (CO(2)) is a promising candidate. However, limited experimental data currently stymie evaluation of its performance in industrial applications. In this paper, we employ atomistic force fields and the configurational-bias Monte Carlo technique to study the vapour-liquid equilibrium of this mixture. We also characterize the microscopic structure of the mixture, which is not readily available from experiments. At 272 K and 11.55 bar, the average coordination number of the first solvation shell of R134a is 11 and that of CO(2) is eight. CO(2) does not alter the structure of R134a, but its structure is slightly changed, due to the presence of R134a. All pair interactions are sensitive to pressure and are more structured at lower pressure. CO(2) prefers to form clusters of two in the mixture and highly extended or percolating clusters are not found. 相似文献
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WAN Jun LI Chun-li LI Xue-mei ZHANG Shu-sheng~ College of Chemistry Molecular Engineering Qingdao University of Science Technology Qingdao P.R. China 《高等学校化学研究》2006,22(4)
IntroductionTriazole derivatives have become the most rapidlyexpanding group of antifungal compounds with advanta-ges of lowtoxicity, high oral bioavailability and broad-spectrum antifungal activity, which can be used againstfungi including most yeasts an… 相似文献
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Meng ZHANG Da Li YIN Ji Yu GUO Xiao Tian LIANG Institute of Materia Medica Chinese Academy of Medical Science & Peking Union Medical College Beijing 《中国化学快报》2005,16(7)
Numerous reports have described the semisynthesis of paclitaxel and its anologues from different taxoids 1. However, to the best of our knowledge almost all taxoids have a C-1-hydroxyl. Heretofore, the semisynthesis from taxinine, an abundant natural taxoid lacking of C-1-hydroxyl, has only reached the point of C-13 ketone intermediate 2. We have also encountered difficulties in reducing C-13 ketone to corresponding α- hydroxy group using the same conditions as in total synthesis of paclita… 相似文献
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《Journal of organometallic chemistry》1987,331(1):113-119
The course of palladium-catalyzed oxidation of a terminal alkene by t-BuOOH or by O2/H2O is greatly modified when the allylic carbon bears a p-toluenesulfonyl substituent, and allylic oxidation results. Mechanistic explanations of this observation are proposed. 相似文献
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It was discovered by means of dynamic NMR that the 1-(cis-1-methylprop-1-en-1-yl)-1,2-dimethylacenaphthylenonium ion generated under conditions of “long life” for carbocations underwent fast (ΔG#35.8 kJ mol?1 at ?103°C) degenerate 1,2-shift of the cis-dimethylvinyl group. Quantum-chemical calculations by DFT method predict lower rate of 1,2-shift for the trans-dimethylvinyl group compared to cis-dimethylvinyl group and dependence on the cations conformation of the rates of these processes and of the rearrangement mechanism into the ions of phenalenyl type. 相似文献
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R. R. Gataullin R. R. Ishberdina A. M. Sotnikov I. B. Abdrakhmanov 《Russian Journal of Applied Chemistry》2005,78(3):438-440
Alkenylation of 6-methyl-2-(2-cyclohexen-1-yl)- and 2-(1-cyclohexen-1-yl)anilines with piperylene in the presence of AlCl3 and transformation of the resulting cyclohexenylanilines into carbazole structures were studied.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 441–443.Original Russian Text Copyright © 2005 by Gataullin, Ishberdina, Sotnikov, Abdrakhmanov. 相似文献
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M. V. Leonova M. R. Baimuratov Yu. N. Klimochkin 《Russian Journal of Organic Chemistry》2014,50(9):1268-1271
Wittig rearrangement of an allyl benzyl ether containing an adamantane fragment has been studied. 1-[(1E)-3-(Benzyloxy)prop-1-en-1-yl]adamantane reacts with butyllithium to give [2,3]- and [1,2]-rearrangement products. The [2,3]-rearrangement product is a mixture of threo and erythro diastereoisomers, the latter prevailing. 相似文献