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21.
T. N. Aksamentova A. V. Knizhnik O. A. Tarasova A. I. Mikhaleva B. A. Trofimov 《Russian Chemical Bulletin》1999,48(9):1664-1669
Dipole moments of the molecules ofO-vinyl- andO-ethylacetoximes in octane and THF were measured at different temperatures. In octane, the equilibrium mixture of stableO-vinylacetoxime conformers consists of forms with different polarity. Polarity of these conformers, which are due to rotation
about the C−O and N−O bonds, is mainly determined by the relative position of the lone electron pairs of nitrogen and oxygen
atoms. The fraction of the polar conformer increases as temperature increases, as well as on going from octane to THF. Saturation
of the vinyl group in theO-vinylacetoxime molecule nearly halves the molecular dipole moment in the nonpolar medium, which radically differentiates
this compound from vinyl ethers.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1685–1690, September, 1999. 相似文献
22.
A. I. Mikhaleva R. N. Nesterenko A. M. Vasil'tsov G. A. Kalabin É. N. Deryagina N. A. Korchevin N. I. Golovanova 《Chemistry of Heterocyclic Compounds》1992,28(5):599-601
The reaction of methyl-2-selenienylketoxime with acetylene in KOH-DMSO gives 2-(2-selenienyl)pyrrole and its 1-vinyl derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 708–710, May, 1992. 相似文献
23.
S. E. Korostova B. A. Trofimov L. N. Sobenina A. I. Mikhaleva M. V. Sigalov 《Chemistry of Heterocyclic Compounds》1982,18(10):1043-1045
2-(1-Naphthyl)- and 2-(2-naphthyl)pyrroles and their 1-vinyl derivatives were synthesized in 22–64% yields by the reaction of 1- and 2-acetylnaphthalene oximes with acetylene at both atmospheric pressure and elevated pressures in an alkali metal hydroxide-dimethyl sulfoxide system.See [1] for communication 22.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1351–1353, October, 1982. 相似文献
24.
25.
The synthesis of 2-methyl-3-(2-propenyl)pyrrole () and E- and Z-2-methyl-3-(1-propenyl)pyrroles () via the reaction of 3-butenyl methyl ketoxime () with acetylene in the KOH-DMSO system is reported. 相似文献
26.
Annenkov V.V. Filina E.A. Danilovtseva E.N. Zinchenko S.V. Mikhaleva A.I. 《Journal of Sol-Gel Science and Technology》2003,27(2):163-166
The formation of alumina particles from aluminum salts in the presence of poly(1-vinylimidazole) was investigated by quantitative 27Al NMR, potentiometry and FTIR spectra. The interaction of poly(1-vinylimidazole) with aluminum chloride and nitrate in an aqueous medium stabilizes [AlO4Al12(OH)24]7+ and less ordered polymeric particles. The addition of NaOH (NaOH: Al 2) results in water-insoluble organic/inorganic hydrogen-bonded composites. Stabilization of the complexes is realized by cooperative hydrogen N···H—O—Al bonds, without N Al donor-acceptor interactions. 相似文献
27.
B. A. Trofimov S. E. Korostova A. I. Mikhaleva L. N. Balabanova A. N. Vasil'ev 《Chemistry of Heterocyclic Compounds》1977,13(2):172-173
The hydrogenation of 1-vinylpyrroles over Raney nickel in ethanol at 50–90°C proceeds exclusively at the 1-vinyl group and leads to the formation of 1-ethylpyrroles in 80–90% yields. The IR and PMR spectra are presented.Translated from Khimiya Geterotsilicheskikh Soedinenii, No. 2, pp. 215–216, February, 1077. 相似文献
28.
The reaction of 1-phenyl-3-methyl-4-benzal-5-pyrazolone with urea does not lead to closing of a pyrazolo[3,4-d]pyrimidine ring because of the reduced tendency of the carbonyl group of the pyrazolone to participate in cyclization reactions. The expected 1,4-diphenyl-3-methyl-6-oxo-4,5,6,7-tetrahydropyrazolo[3,4-d]pyrimidine was obtained by condensation of 1-phenyl-3-methyl-5-aminopyrazole with benzalbisurea and was dehydrogenated to the dihydro derivative. 相似文献
29.
Chipanina N. N. Turchaninov V. K. Vorontsov I. I. Antipin M. Yu. Stepanova Z. V. Sobenina L. N. Mikhaleva A. I. Trofimov B. A. 《Russian Chemical Bulletin》2002,51(1):111-116
The molecular structure of 2-(2-benzoyl-1-phenylethenyl)-5-phenylpyrrole and 2-(2-furoyl-1-phenylethenyl)-5-phenylpyrrole was studied by X-ray diffraction analysis at 110 K and quantum chemistry methods (B3LYP/6-31G*). In the crystalline state, both compounds have cyclic structures closed by strong intramolecular hydrogen bond N—H...O. Canonic zwitterionic structure contributes largely to the ground state of the molecules. This is probably due to synergism of the H-bonding and -electron interactions. 相似文献
30.