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Yang Shi Jing Zhi Sun Anjun Qin 《Journal of polymer science. Part A, Polymer chemistry》2017,55(4):616-621
As an emerged efficient polymerization methodology, the click polymerization plays a significant role in the area of polymer and materials sciences. Similar to the click reaction, the click polymerization enjoys the advantages of high efficiency, mild reaction conditions, and high regio- and stereo-selectivity etc. In this highlight, we summarize the recent progress on click polymerizations, with focus on the alkyne-based ones. The challenges and opportunities in this area are also briefly discussed. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 616–621 相似文献
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Liang-Deng Nie Fei-Feng Wang Wei Ding Xiao-Xin Shi Xia Lu 《Tetrahedron: Asymmetry》2013,24(11):638-642
A novel azide-free asymmetric synthesis of oseltamivir phosphate 1 (Tamiflu®) starting from Roche’s epoxide is described. Roche epoxide 2 was converted into N-acetyl aminoalcohol 3 in 95% yield via a BF3·OEt2-catalyzed epoxide-opening with acetonitrile as a nucleophile. Compound 3 was then transformed into a methanesulfonate 4 in 98% yield. Compound 4 was converted into aziridine 5 in 91% yield. Aziridine 5 was subsequently converted into oseltamivir phosphate 1 via two paths (a and b). In the path a, compound 5 underwent aziridine-opening with diallylamine as a nucleophile to afford compound 7 in 93% yield; compound 7 could then be converted into oseltamivir phosphate 1 in 88% yield. In path b, compound 5 underwent aziridine-opening with isopropyl 2,2,2-trichloroacetimidate as a nucleophile to afford compound 8 in 94% yield, which was then converted into oseltamivir phosphate 1 in 82% yield. 相似文献
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A series of (3-oxo-1,3-diaryl) propylpropanedinitriles were synthesized by Michael addition reaction of chalcones and malononitriles in the presence of potassium fluoride on alumina. 相似文献
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The effect of seasonality and periodicity on plankton dynamics is investigated. Periodic variations are added to two different parameters of the plankton ecosystem: the growth rate of phytoplankton and the death rate of the zooplankton. The dynamic behaviors of the system is simulated numerically. A variety of complex population dynamics including chaos, quasi-periodicity, and periodic resonance are obtained. Our result reinforces the conjecture that seasonality and periodicity are crucial to plankton dynamics. 相似文献
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