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1.
N. A. Klyuev R. A. Khmel'nitskii G. A. Mal'tseva L. N. Zhukauskaite A. N. Kost 《Chemistry of Heterocyclic Compounds》1973,9(7):895-900
The mass spectra of the following methyl-substituted hydroxyquinolines have been studied in the range of energies of the ionizing electrons of 15–50 eV: 2-hydroxy-4-methylquinoline, 6-hydroxy-2-methylquinoline, 6-hydroxy-4-methylquinoline, 8-hydroxy-2-methylquinoline, 8-hydroxy-4-methylquinoline, 2,6-dihydroxy-4-methylquinoline, and 4,6-dihydroxy-2-methylquinoline. It has been shown that the processes of dissociative ionization for the series of compounds investigated take place exclusively from the keto forms of the molecular ions. The stability to electron impact is determined largely by the degree of enolization of the structures considered. The values of the selective decomposition are given and a scheme is proposed for the identification of the isomeric methyl-substituted hydroxyquinolines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 972–978, July, 1973. 相似文献
2.
A. V. Shastin T. I. Godovikova S. P. Golova M. V. Povorin D. E. Dmitriev M. O. Dekaprilevich Yu. A. Strelenko Yu. T. Struchkov L. I. Khmel'nitskii B. L. Korsunskii 《Chemistry of Heterocyclic Compounds》1995,31(5):601-609
2-R-amino-4,6-bis (trinitromethyl)-1,3,5-triazines have been synthesized, and their structures have been established. Dynamic13C NMR spectroscopy has been used to measure the rotational barriers of the tertbutylamino group around the C(2)-NHBu-t bond in 2-(tert-butylamino)-4,6-dichloro-1, 3, 5-triazine and 2-(tertbutylamino)-4,6-dimethoxy-1,3,5-triazine. X-ray diffraction was used to investigate the structure of 2-(tertbutylamino)-4,6-bis (trinitromethyl)-1,3,5-triazine. From the results obtained in this work it has been concluded that the bond between the NHBu-t group and the triazine ring has a partial double-bond character.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117913. Translated from ] Khimiya Geterotsikiicheskikh Soedinenii, No. 5, pp. 679–688 May, 1995. Original article submitted March 7, 1995. 相似文献
3.
A. S. Ermakov S. A. Serkov V. A. Tartakovskii T. S. Novikova L. I. Khmel'nitskii 《Russian Chemical Bulletin》1995,44(4):699-701
TheN-nitro derivatives of the products of the condensation of formaldehyde with sulfamic acid derivatives and guanidine, nitroguanidine, 3,4-diaminofurazan, and 3-amino-4-methylfurazan have been synthesized.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 719–721, April, 1995. 相似文献
4.
The possibility was studied of using bromine derivatives, analogous to those of chlorines, in the synthesis of 1,2-dialkyldiaziridines, and it was shown that NaOBr successfully replaces NaOCl, while RNHBr gives good results in water in the presence of an excess of amine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2090–2094, September, 1989. 相似文献
5.
P. B. Terent'ev O. A. Solov'ev R. A. Khmel'nitskii S. P. Gromov R. S. Sagitullin 《Chemistry of Heterocyclic Compounds》1982,18(6):578-580
Peaks of [M — NO]+ and [M — NO2]+ ions are characteristic for the mass spectra of nitroindolizines, whereas peaks of ions of the indole type, viz., [M — HCN]+ and [M- H,- HCN]+ (for alkylindoles), are not characteristic. In the mass spectra of nitroindoles the latter ions give more intense peaks, while the loss of a nitro group or its rearrangement is a considerably less significant process. When a dialkylamino group is introduced in the nitroindolizine molecule, the primary processes in the fragmentation of such compounds are due to fragmentation of the alkylamino group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 765–768, June, 1982. 相似文献
6.
O. A. Rakitin V. A. Ogurtsov T. I. Godovikova L. I. Khmel'nitskii 《Russian Chemical Bulletin》1990,39(7):1472-1474
We have studied the reactions of aromatic nitrile oxides with nitrogen monoxide and nitrogen sesquioxide. It was shown that nitrogen monoxide removes an oxygen atom from the nitrile oxide with formation of the corresponding nitrile and nitrogen dioxide. The reaction products with nitrogen sesquioxide are formed as a result of reactions of the nitrile oxide with nitrogen monoxide and nitrogen tetroxide.For previous communication, see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1623–1625, July, 1990. 相似文献
7.
P. B. Terent'ev R. A. Khmel'nitskii N. A. Klyuev A. B. Belikov V. V. Dorogov 《Chemistry of Heterocyclic Compounds》1973,9(1):60-62
The mass spectra of dimethylbenzyl- and dimethyldibenzylpyridines at different ionizing electron energies were investigated. The anomalously low intensities of the molecular ion peaks of 3,4-dibenzylpyridines, as compared with the 2,5-isomers, and the greater probability of the formation of primary (M-2)+ ions in the mass spectra are explained by the synchronous loss of a neutral H2 particle and the formation of cyclic fragment ions from the weakly excited molecular ions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 70–73, January, 1973. 相似文献
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10.
Synthesis and structure of 2,5,7,10-tetramethyl-2,4,8,10-tetraazabicyclo[4.4.0]decane-3,9-dione 总被引:1,自引:0,他引:1
M. O. Dekaprilevich A. N. Kravchenko L. I. Khmel'nitskii O. V. Lebedev Yu. T. Struchkov Yu. A. Strelenko 《Russian Chemical Bulletin》1995,44(1):131-133
2,5,7,10-Tetramethyl-2,4,8,10-tetraazabicyclo[4.4.0]decane-3,9-dione, a regioisomer of the previously known 2,5,7,8-tetramethyl-2,4,8,10-tetraazabicyclo[4.4.0]decane-3,9-dione, has been synthesized, and its structure has been established by X-ray diffraction analysis. The bicyclic system of this molecule is formed by two heterocyclescis-annelated through the C(1)-C(6) bond. The relative configurations of the asymmetric centers areS for C(5), andR for C(7). In the monohydrate crystal studied, the molecules are linked by O...H-Ow and O...H-N type H-bonds forming a three-dimensional framework.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 136–138, January, 1995. 相似文献