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V. A. Zyryanov N. A. Klyuev V. L. Rusinov I. Ya. Postovskii A. B. Belikov L. F. Lusev 《Chemistry of Heterocyclic Compounds》1980,16(4):437-442
Depending on the reaction conditions, the nitration of 1-phenyl-5-styryltetrazole (I) with nitric acid and nitrating mixture give 1-(4-nitrophenyl)-5-styryltetrazole, 1-(4-nitrophenyl)-5-(4-nitrostyryltetrazole), and 1-(2,4-dinitrophenyl)-5-(4-nitrostyryl) tetrazole. The structures of the compounds obtained have been established by an analysis of their mass spectra and of the mass spectra of model compounds. The positions and sequences of entry of the nitro groups have been determined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 558–563, April, 1980. 相似文献
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Kang Y Zyryanov GV Rudkevich DM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(6):1924-1932
The use of simple calix[4]arenes for chemical conversion of NO2/N2O4 gases is demonstrated in solution and in the solid state. Upon reacting with these gases, calixarenes 1 encapsulate nitrosonium (NO+) cations within their cavities with the formation of stable calixarene-NO+ complexes 2. These complexes act as encapsulated nitrosating reagents; cavity effects control their reactivity and selectivity. Complexes 2 were effectively used for nitrosation of secondary amides 5, including chiral derivatives. Unique size-shape selectivity was observed, allowing for exclusive nitrosation of less crowded N-Me amides 5 a-e (up to 95 % yields). Bulkier N-Alk (Alk>Me) substrates 5 did not react due to the hindered approach to the encapsulated NO+ reagents. Robust, silica gel based calixarene material 3 was prepared, which reversibly traps NO2/N2O4 with the formation of NO+-storing silica gel 4. With material 4, similar size-shape selectivity was observed for nitrosation. The N-Me-N-nitroso derivatives 6 d,e were obtained with approximately 30 % yields, while bulkier amides were nitrosated with much lower yields (<8 %). Enantiomerically pure encapsulating reagent 2 d was tested for nitrosation of racemic amide 5 t, showing modest but reproducible stereoselectivity and approximately 15 % ee. Given high affinity to NO+ species, which can be generated by a number of NOX gases, these supramolecular reagents and materials may be useful for NOX entrapment and separation in the environment and biomedical areas. 相似文献
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Zyryanov GV Kang Y Stampp SP Rudkevich DM 《Chemical communications (Cambridge, England)》2002,(23):2792-2793
Reaction of NO2 with simple calix[4]arenes in chloroform in the presence of a Lewis acid rapidly results in intense coloration caused by the encapsulation of nitrosonium cation. 相似文献
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Khabibulina I. V. Trifonov R. E. Volovodenko A. P. Eremenkova M. S. Chupakhin O. N. Rusinov V. L. Zyryanov G. V. Ostrovskii V. A. 《Russian Journal of Organic Chemistry》2004,40(3):426-430
The acidity and basicity constants of isomeric phenyl(aryl)-1,2,4-triazin-3- and -5-ones in aqueous solution were determined by spectrophotometry: pK
a = 7.3–6.2; pK
BH+= 0.1 to –2.2. 1,2,4-Triazin-3-ones are weaker bases than the corresponding 1,2,4-triazin-5-ones. According to the AM1 calculations, the most thermodynamically favorable tautomer in the gas phase is the oxo form: namely, 2H-tautomers of the neutral bases and 2,4-H,H
+-tautomers of the conjugate acids. 相似文献
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Nemtsev I. V. Shabanova O. V. Tambasov I. A. Ivanenko A. A. Cherepakhin A. V. Shestakov N. P. Zyryanov V. Ya. 《Journal of Structural Chemistry》2021,62(4):641-650
Journal of Structural Chemistry - Series of high-quality spherical poly(methyl methacrylate) particles with a polydispersity less than 5% are prepared by chain-growth emulsifier-free controlled... 相似文献
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Rana Chatterjee Satyajit Samanta Anindita Mukherjee Sougata Santra Grigory V. Zyryanov Adinath Majee 《Tetrahedron letters》2019,60(3):276-283
We have observed that the allylic zinc halide under identical reaction conditions acts in different modes for different electrophiles. For Ts-aziridines the halide part of the allylic halide has been introduced as a nucleophile and for the carbonyl compounds the simple allylation reaction occurs. To the best of our knowledge this is the first report where the allylic zinc halide is the source of halide acting as nucleophile. The main advantages of the present procedure are easy to handle, no need of inert atmosphere, mild reaction conditions, and applicability to a wide variety of substrates for aziridines and carbonyl compounds. 相似文献
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Krinochkin A. P. Shabunina O. V. Savchuk M. I. Kudryashova E. A. Rybakova S. S. Ladin E. D. Kopchuk D. S. Zyryanov G. V. Chupakhin O. N. 《Russian Journal of Organic Chemistry》2022,58(6):917-919
Russian Journal of Organic Chemistry - An efficient synthetic approach to 3-(4-carboxyphenyl)pyridine-2,6-dicarboxylic acid has been developed on the basis of “1,2,4-triazine”... 相似文献