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1.
N. S. Prostakov B. Kh. Sisimbina S. A. Soldatova V. P. Shalimov K. G. Montenegro N. I. Leonova L. A. Murugova 《Chemistry of Heterocyclic Compounds》1982,18(12):1290-1294
Isomeric (with respect to the position of the nitrogen atom) azafluorenes were cyanoethylated. The resulting 9,9-bis(-cyanoethyl) derivatives were converted to the corresponding dibasic acids and their diesters. The latter were subjected to the Dieckmann reaction to obtain spiro compounds with azafluorene and cyclohexene fragments. The analogous spirans with 1,3-dioxalane and 1,3-dioxane rings were obtained from 3-methyl-2-azafluorenone.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1668–1672, December, 1982. 相似文献
2.
The behavior of electrochemical cells Pt(sponge)/Na5TbSi412/Na0.65Co2(cell I) and Pt(sponge)/Na5TbSi412/Pt(sponge) (cell II) is studied by, respectively, potentiometric and impedance methods in oxygen and argon atmospheres at 50–300°C. Dependence of potential of cell I on the oxygen concentration is affected by the grain size of platinum sponge and the temperature. At 50–200°C the coarse-grained platinum electrode in contact with solid electrolyte Na5TbSi412 exhibits an oxygen function characterized by the potential-determining reaction 2(g) + 2 + 2 = –
2 + –. An impedance method shows the triple-phase boundary 2, Pt(sponge)/Na5TbSi412 to be reversible with respect to oxygen. The reversibility is realized by minority charge carriers in the solid electrolyte, i.e. by oxygen ions. 相似文献
3.
A.N. Nesmeyanov E.V. Leonova N.S. Kochetkova A.I. Malkova 《Journal of organometallic chemistry》1975,96(2):271-274
A method is described for the preparation of 1,2-diacetylferrocene, in which ferrocene is acetylated with acetyl chloride in the presence of AlCl3 in methylene chloride. Addition of the ferrocene to an excess of the acetylation mixture over a prolonged period was found to be most favourable. The 1,2-diacetylferrocene formed proved to be free of the 1,3-isomer. It was reduced with LiAlH4/AlCl3 to 1,2-diethylferrocene. 相似文献
4.
L.O. Atovmyan O.S. Filipenko V.I. Ponomarev L.S. Leonova E.A. Ukshe 《Solid State Ionics》1984,14(2):137-142
Conductivity measurements of the crystals of the N5RESi4O12 family, where RE=Sm→Lu, have been made. A reversible phase transition R32Rc has been established. The conductive channels have been determined using a high temperature X-ray structural analysis of the Na5RESi4O12 crystals, as well as the ion exchanged Ag phase. 相似文献
5.
Zyubina T. S. Shilov G. V. Dobrovol'skii Yu. A. Leonova L. S. Mebel' A. M. 《Russian Journal of Electrochemistry》2003,39(4):376-385
Orthoperiodic and orthotelluric acids, their salts MIO6H4 (M = Li, Rb, Cs) and CsH5TeO6, and dimers of the salt · acid type are calculated within density functional theory B3LYP and basis set LanL2DZ complemented by the polarizationd,p-functions. According to calculations, the salt · acid dimerization is energetically favorable for compounds MIO6H4 · H5IO6 (M = Rb, Cs) and CsIO6H4 · H6TeO6. The dimerization energy is equal to 138–146 kJ mol–1. With relatively small activation energies equal to 4 kJ mol–1 (M = Li) and 11 kJ mol–1 (M = Rb, Cs), possible is rotation of octahedron IO6 relative to the M atom in monomers of salt molecules. The proton transfer along an octahedron occurs with activation energies of 63–84 kJ mol–1. The activation energy for the proton transfer between neighboring octahedrons of the type salt · acid acid · salt equals 8–17 kJ mol–1. Quantum-chemical calculations nicely conform to x-ray diffraction and electrochemical data. 相似文献
6.
Larionov S. V. Leonova T. G. Glinskaya L. A. Klevtsova R. F. Platonov V. E. Maksimov A. M. Fadeeva V. P. Batrachenko N. I. 《Russian Journal of Coordination Chemistry》2000,26(12):861-865
Compounds (CH3)2Sn(C12F9S)2 (I), (CH3)2Sn(C10F7S)2 (II), and (C2H5)2Sn(C10F7S)2 (III) were synthesized. Single crystals of Iwere grown and structurally characterized using X-ray diffraction analysis (1590 reflections, R = 0.0209). The crystals are orthorhombic, a = 40.848(8) Å, b = 6.058(1) Å, c = 11.183(2) Å, V = 2767(1) Å3, (calcd.) = 2.024 g/cm3, space group Pbcn, Z = 4. The structure is built from monomeric molecules. The coordination polyhedron of the Sn atom (the SnC2S2 core) is a distorted tetrahedron. Compounds I–III are volatile when heated in vacuo. Thermolysis of these compounds results in SnO2 (in air) or SnS2 (in argon). 相似文献
7.
L. A. Frolova L. S. Leonova A. A. Arslanova Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2013,49(8):822-826
Effective catalytic systems based on Pt/CeO2-C were prepared. The use of a cerium oxide addition in the substrate stabilized the platinum catalysts against their poisoning with carbon monoxide at room temperature. 相似文献
8.
Leonova M. V. Belaya N. V. Baimuratov M. R. Klimochkin Yu. N. 《Russian Journal of Organic Chemistry》2018,54(11):1643-1651
Russian Journal of Organic Chemistry - Mono- and disubstituted aziridines derived from sterically hindered olefins of the adamantane series are synthesized. The opening of the aziridine ring under... 相似文献
9.
Zhanna A. Krasnaya Vladimir A. Kuz’min Lyubov V. Litvinkova Evgeniya O. Dorofeeva Sergei G. Zlotin 《Mendeleev Communications》2013,23(4):212-214
New bischromophoric dyes (thiacarbocyanine and thiadicarbocyanine) containing coumarin moieties at each of the two benzothiazole systems, as well as monomethinecyanine containing coumarin moiety at only one heterocyclic system, manifest significant batho-chromic shift compared to relative coumarin-free dyes. 相似文献
10.
M. V. Leonova M. Yu. Skomorokhov I. K. Moiseev Yu. N. Klimochkin 《Russian Journal of Organic Chemistry》2015,51(12):1703-1709
A one-pot procedure has been proposed for the synthesis of amines directly from cage hydrocarbons. A number of cage amines have been synthesized by treatment of adamantane, its homologs, and structurally related cage hydrocarbons with nitric acid in acetic acid and subsequent addition of urea and heating. 相似文献