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1.
2.
V. V. Semenov V. S. Bogdanov B. S. Él'yanov L. G. Mel'nikova S. A. Shevelev V. M. Zhulin A. A. Fainzil'berg 《Chemistry of Heterocyclic Compounds》1982,18(8):859-864
The quaternization of 1- and 2-acetonyl-5-R-tetrazoles, as well as dimethyltetrazole, was accomplished under high pressure conditions (5000–14,000 kgf/cm2) by means of bromoacetone and methyl iodide and at atmospheric pressure and room temperature under the influence of methyl fluorosulfate. The structure of the salts were ascertained by 13C NMR spectroscopy, and the principles of the change in the chemical shifts and the spin-spin coupling constants during quaternization and protonation of the tetrazoles were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1118–1124, August, 1982. 相似文献
3.
V. V. Sharutin O. K. Sharutina L. G. Mel'nikova G. K. Fukin L. N. Zakharov A. I. Yanovsky Yu. T. Struchkovdt 《Russian Chemical Bulletin》1996,45(8):1977-1980
Tetraphenylantimony hydrogen phthalate, Ph4SbOC(O)C6H4000H-o, was prepared by the reaction of pentaphenylantimony with phthalic acid. According to the data of X-ray structural analysis, the resulting compound is a trigonal-bipyramidal complex of antimony with three phenyl groups in equatorial positions; the fourth phenyl group and the carboxyl fragment are in axial positions. The CSbO angle is 177.5(1)° the Sb-C(Ph)eq and Sb-C(Ph)ax distances are 2.099(4)-2.177(4) A and 2.129(4) A, respectively. The H atom of the free carboxyl group and the carbonyl O atom of another carboxylate group form an intramolecular hydrogen bond.DeceasedTranslated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 2082–2085, August, 1996. 相似文献
4.
S.D ShaposhnikovS.V Pirogov S.F Mel'nikova I.V TselinskyC Näther T GraeningT Traulsen W Friedrichsen 《Tetrahedron》2003,59(7):1059-1066
Interaction of 3,4-diacylfuroxans with hydroxylamine hydrochloride results in the formation of substituted 4,5-bis (hydroximino)-4,5-dihydroisoxazoles, whereas the reaction of 3,4-bis(4-methylfurazanoyl-3)furoxan with hydrazine hydrate in acetic acid affords 3-[4,5-bis(hydroximino)-4,5-dihydro-1H-pyrazol-3-yl]-4-methylfurazan. N-Acyl-, N-nitro-, N-alkyl- and N-adamantyl derivatives of the latter compound have been synthesized. X-Ray structure determinations together with density functional theoretical calculations are reported. 相似文献
5.
The synthesis of 2-alkyl(dialkyl)amino-4-chloro-sym-triazine derivatives of hydroxylamine, N-methylhydroxylamine, and N-phenylhydroxylamine has been effected and their properties have been studied. The thermal and catalytic polycondensation of the 2-alkyl(dialkyl)amino-4-chloro-6-N-phenyl(methyl)hydroxyamino-sym-triazines accompanied by the liberation of hydrogen chloride and the formation of linear polycondensates with 3–4 members has been observed.For part IX see [9]. 相似文献
6.
M. A. Kirpichenok D. S. Yufit L. M. Mel'nikova Yu. T. Struchkov L. K. Denisov I. I. Grandberg 《Chemistry of Heterocyclic Compounds》1990,26(8):852-857
The photocycloaddition of trans-stilbene to 7-diethylaminocoumarin, 4-methyl-7-diethylaminocoumarin, and 4-(N-morpholino)-7-diethylaminocoumarin was investigated. Adducts involving stereospecific (2+2)-cycloaddition at the 3–4 bond were isolated. On the basis of the PMR spectra and an x-ray diffraction study, it was established that the phenyl groups in the cycloadducts occupy 1-endo and 2-exo positions.For Communication 4, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1022–1027, August, 1990. 相似文献
7.
The article presents the results of an investigation of the quantum yield and absolute population of the vibrational levels of electronically excited states A2 (v 25), B2 (v 15) of the CN radical and B3g (v 12) of the N2 molecule in nitrogen-helium afterglow cooled by liquid nitrogen at a total pressure of the mixture of (12–20) mm Hg. The rotational temperature of the cold gas was measured. The content of carbon impurity in the system was measured by the spectral method. A study was made of the kinetics of the decay of afterglow, from which the relaxation time was determined and the cross section of exchange of vibrational quanta between N2 and CN molecules was estimated. The data obtained were compared with the results of investigating nitrogen-helium afterglow under room-temperature conditions.300th Anniversity of Reunion of Ukraine with Russia Dnepropetrovsk State University.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 52–59, April, 1976. 相似文献
8.
The reaction of dihydroquercetin, quercetin, and rutin with Cu(II) acetate in aqueous solution is studied. Quercetin and dihydroquercetin form complexes with Cu. The water-insoluble complexes are characterized as chelates of the 3,4-positions of the main -pyrone ring. Electronic spectroscopy showed the presence of stable polynuclear rutin complexes of composition rutin :Cu = 1:x, where x > 2. 相似文献
9.
M. A. KirpichËnok L. M. Mel'nikova L. K. Denisov I. I. Grandberg N. P. Akimova 《Chemistry of Heterocyclic Compounds》1989,25(1):23-29
The photochemical reactions of 4-methyl-7-diethylaminocoumarin with the dimethyl ester of acetylenedicarboxylic acid, diethyl ester of maleic acid, and N-phenylmaleimide in the presence of oxygen and acetophenone give products of the heterocyclization at C(6) and C(8) of coumarin fragment with participation of the diethylamino group. The stereochemical structure of the compounds synthesized was demonstrated using PMR spectroscopy. A mechanism was proposed for this reaction involving the formation of an -amino radical and its addition to the acetylene or olefin, accompanied by attack on the aromatic ring with subsequent aromatization.See [1] for Communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 30–36, January, 1989. 相似文献
10.
Mel'nikova N. B. Sokolov V. G. Molvina L. I. 《Russian Journal of Applied Chemistry》2004,77(7):1142-1146
A study was made of neutralization and clarification of wastewater from silicate production, which exhibits buffer properties. The promise of a two-stage procedure involving the primary thickening of the dispersed phase, followed by separation of the dispersed phase and water by flotation, was elucidated. The choice of the polymeric reagent and its concentration was substantiated. 相似文献