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81.
Su Yuan Zhou Xiao Yan Wei 《中国化学快报》2007,18(3):319-321
1H NMR has been used to determine the 2-,4-vinyl orientation of heme active site from oxidized mouse neuroglobin (mNgb).The NOEs between 3-methyl and Hα, Hβ of 2-vinyl, together with the NOEs between 5-methyl and Hα, Hβ of 4-vinyl, allowed the unambiguous determination of trans and cis orientations for the 2- and 4-vinyl groups in the mNgb, respectively. 相似文献
82.
Vinyl p-aminophenylsulfone and methyl vinyl sulfone were shown to react, as Michael acceptors, with a broad range of secondary and primary amines using Amberlyst as catalyst. The reactions occurred, generally, with high yields and in a short time. 相似文献
83.
S. Lengvinaite M. Sangermano A. Priola S. Grigalevicius V. Getautis 《European Polymer Journal》2007,43(2):380-387
New carbazole monomers were synthesized and their cationic photopolymerization investigated. The monomers contain in each molecule two pendant carbazole groups and two functional groups reactive towards cationic photopolymerization. The investigated reactive groups were epoxy, oxetane or vinyl ether. Each type of monomer contains a spacer group namely ethylene oxide segment. The UV curing kinetics of the different monomers was monitored by real time FT-IR (RT-FTIR) analysis and the thermal properties evaluated by DSC. 相似文献
84.
85.
The suitability of ormosils as photonic materials was investigated. Vinyl and phenyl silicates were synthesised below 100°C. A detailed assignment of mid-infrared vibrational absorption bands is given. This allowed assignment of overtone and combination bands in the near-infrared region and an assessment of residual water contamination, which is low and can be expelled by evacuation. These ormosils have low intrinsic and extrinsic optical absorption in the visible spectral region and at useful wavelengths in the near-infrared. 相似文献
86.
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88.
Vera V. Astakhova Bagrat A. Shainyan Mikhail Yu. Moskalik Irina V. Sterkhova 《Tetrahedron》2019,75(33):4531-4541
The reaction of trimethyl(vinyl)silane 1 and dimethyl(divinyl)silane 2 with various sulfonamides in the oxidative system (tert-BuOCl + NaI) has been studied and shown to be an efficient approach for the synthesis of silylated N-heterocycles. Triflamide demonstrated the reactivity principally different from that of arenesulfonamides. With silane 1, it afforded the products of iodochlorination and bis(triflamidation) (major), whereas arenesulfonamides gave N-arenesulfonylaziridines in up to 91% yield. Silane 2 with arenesulfonamides yielded the products of mono and bis(iodochlorination), mono and bis(aziridination), and 3,5-diiodo-4,4-dimethyl-1-(arylsulfonyl)-1,4-azasilinanes. By contrast, triflamide, apart from the products of halogenation and iodotriflamidation, unexpectedly gave 3-(trifluoromethylsulfonyl)-5-(triflamido)oxazolidine as the main product. The structure of most heterocyclic products is proved by X-ray analysis. The effect of the silyl group in the substrate and of the substituent in the reagent on the course of oxidative sulfamidation is discussed by comparing with all-carbon analogues. 相似文献
89.
Ping-ping Tian Hong-qing Xiao Lu Wang Yingxin Yu Yangen Huang 《Tetrahedron letters》2019,60(15):1015-1018
Terminal vinyl triflones served as excellent Michael addition acceptors which readily reacted with difluoromethylene phosphabetaine and di- or mono-fluoroalkyl bromides to afford compounds containing CF2 or CF groups. This fluoroalkylation is characterized by mild reaction conditions, ready availability of reagents and excellent functional-group tolerance. 相似文献
90.
Suitably protected carbohydrates were joined together using 1,5-disubstituted 1,2,3-triazolylmethylene (1,5-DTM) linkers. The DTM linker was built by the 1,3-dipolar cycloaddition reactions of a series of sugar azides with vinyl sulfonylmethylene-modified furanose or pyranose under metal free conditions. Three different biodegradable hydroxylammonium based ionic liquids were studied in water as the reaction media. The N,N-dimethyl ethanolammonium formate-water mixture was found to be the best reaction medium because the reaction time was shortened considerably to generate a dozen new 1,5-DTM-linked disaccharides. 相似文献