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81.
Michelle Galgoci Janel E. Davidson Clinton K. Harrington Dennis L. Hasha Christian T. Goralski 《合成通讯》2013,43(17):2477-2483
A simple method for the preparation of the title compounds via the reaction of dimethyl 2-ethenylcyclopropane-1,1-dicarboxylate with 6M ammonia in methanol is described. 相似文献
82.
The reaction of substituted arylboronic acids with 5-bromo-2-methoxytropone catalyzed by palladium(0) complex furnished 5-arylated tropone derivatives in good yield. 相似文献
83.
Shawna M. Liff William T. Pennington Dennis W. Smith Jr. 《Journal of polymer science. Part A, Polymer chemistry》2014,52(2):232-238
A novel class of semifluorinated perfluorocyclohexenyl (PFCH) aryl ether homo/copolymers was successfully synthesized with high yield through the step‐growth polymerization of commercially available bisphenols and decafluorocyclohexene in the presence of a triethylamine base. The synthesized polymers exhibit variable thermal properties depending on the functional spacer group (R). PFCH aryl ether copolymers with random and alternating architectures were also prepared from versatile bis‐perfluorocyclohexenyl aryl ether monomers. The PFCH polymers show high thermal stabilities with a 5% decomposition temperature ranging from 359 to 444 °C in air and nitrogen atmosphere. These semifluorinated PFCH aromatic ether polymers contain intact enchained PFCH olefin moieties, making further reactions such as crosslinking and application specific functionalization possible. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 232–238 相似文献
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85.
A convenient laboratory scale preparation of cyanogen has been developed. This new method generates cyanogen from the pyrolysis of diacetyl-glyoxime which can be easily prepared from glyoxime. 相似文献
86.
Philip J. Hammond C. Dennis Hall 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):351-353
Abstract Cis-1-alkyl (or aryl)-2,5-dimethyl-3-phospholens isomerize to the trans-isomers in deuteriochloroform and the isomerization is probably due to small quantities of phosgene in the solvent. 相似文献
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89.
Han Joong Koh Suk Jin Kang Dennis N. Kevill 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1404-1415
Kinetic and product studies of the solvolyses of acyclic phosphorochloridates are extended to two cyclic diesters, 2-chloro-1,3,2-dioxaphospholane-2-oxide (1) and 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane-2-oxide (2). Slightly faster solvolyses are observed for 1 than for the acyclic dimethyl phosphorochloridate (3), and 2 solvolyzes somewhat slower than 3. An extended Grunwald–Winstein equation treatment shows similar sensitivities to changes in solvent nucleophilicity and solvent ionizing power for 1, 2, and 3, and a concerted SN2 attack is proposed in each case. Product studies for the solvolyses of 2 in aqueous alcohols are presented. 相似文献
90.
Martin Pomerantz Jiping Wang Seeyearl Seong Kyle P. Starkey Long Nguyen Dennis S. Marynick 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):507-508
Abstract Poly(benzo[1,2-b:4,5-b′]dithiophene-4,8-diyl vinylene) (1) has been prepared by the pyrolysis of the precursor polymer 2 and studied. Quantum mechanical calculations on the aromatic and quinoid monomers, oligomers and polymers indicate that 1 is a planar aromatic polymer. 相似文献