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1.
Leonard M Khalilov Ludmila V Parfenova Askhat G Ibragimov Usein M Dzhemilev 《Journal of organometallic chemistry》2004,689(2):444-453
This paper is dedicated to a study of properties of the following novel optically active organoaluminium compounds (OACs): (1S,2S)-l,7,7-trimethyl-2-[(dialkylalumina)oxy]-bicyclo[2.2.1]heptanes and (1S)-N-(dialkylalumina)-6,7-dimethoxy-1-methyl-1,2,3,4- tetrahydroisoquinolines. The synthesis of the chiral OACs was carried out in the reaction of either natural camphor or salsolidine with both AlEt3 and i-Bu2AlH. The main goal of the research was to investigate the stereodifferentiating activity of the chiral OACs in the olefin carbo- and cycloalumination reactions, catalyzed by Cp2ZrCl2. 相似文献
2.
A differential equation is obtained that describes the change in the energy of a charged particle in the field of a slow wave (with phase velocity not equal to unity) as a function of the distance traversed. Analysis of this equation yields the amplitude and period of the change in the particle's energy.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 97–102, February, 1981. 相似文献
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L. M. Khalilov M. É. Adler O. V. Shitikova M. S. Miftakhov G. A. Tolstikov 《Chemistry of Natural Compounds》1991,27(1):108-113
The diastereomeric effects on the13C NMR chemical shifts of thirteen epimeric pairs of 16-aryloxy-11-deoxyprostaglandins of the E1 and F1 series caused by the change in the configuration of the 15-hydroxy group, which are differential parameters for assigning epimers to the 15- and 15-stereochemical series, have been determined.For Communication (VIII), see [1].Institute of Chemistry, Bashkir Scientific Center, Urals Branch, Academy of Sciences of the USSR, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 123–128, January–February, 1991. 相似文献
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Ibragimov A. G. Khafizova L. O. Zagrebel"naya I. V. Parfenova L. V. Sultanov R. M. Khalilov L. M. Dzhemilev U. M. 《Russian Chemical Bulletin》2001,50(2):292-296
A new method for the synthesis of dialkyl(ethyl)alanes by the reaction of EtAlCl2 with -olefins in the presence of Mg and a catalytic amount of Cp2TiCl2 (Ti(OPri)4, Ti(OBun)4) in THF was developed. 相似文献
7.
The effects of ultraviolet-B (UV-B) radiation on plasma membrane of water plant (Elodea canadensis, Vallisneria spiralis) cells were investigated by using microelectrode methods. A fast and reversible depolarization of membrane potential occurs initially during exposure of leaf cells to UV on a white light background, after which a slow phase of depolarization sets in. On action series, UV is pulsed for 15 s, with dark interval of 3 min, no monotonous response of systems on the UV excitation is observed. The action spectrum of the fast UV response lies in the interval of 300-330 nm and that of the slow phase-in the interval of 280-300 nm. The input impedance of membranes remains unchanged during the period of exposure. It is concluded that the H(+)-extruding complex of plant cell plasma membranes really consists of two types of interrelated electronic H(+)-pumps: an H(+)-pump of redox-active nature and the H(+)-pump of the H(+)-ATPase enzyme complex. Clearly, during the exposure of leaf cells to UV light, initially, the H(+)-pump of redox-active nature and then H(+)-ATPase are inhibited. It is proposed that the initial chromophore of UV-B light on plasma membrane can be one of the components of H(+)-pump of redox-active nature. It is probably the molecular of quinone. 相似文献
8.
Dzhemilev U. M. Ibragimov A. G. Khafizova L. O. Khalilov L. M. Vasil"ev Yu. V. Tomilov Yu. V. 《Russian Chemical Bulletin》2001,50(2):297-299
1-Ethyl-2,3-fullerenoaluminacyclopropanes (EtAl)n(2-C60) were synthesized by the reaction of fullerene C60 with an excess of EtAlCl2 in the presence of Mg and using Cp2TiCl2 as the catalyst in a THF--toluene solution at 20 °C. Deuterolysis of fullerenoaluminacyclopropanes afforded a mixture of deuteriofullerenes C60Dm, where m = 6--12. 相似文献
9.
Khafizova L. O. Ibragimov A. G. Yalalova D. F. Borisova A. L. Khalilov L. M. Dzhemilev U. M. 《Russian Chemical Bulletin》2003,52(9):2012-2016
A method for the synthesis of secondary and tertiary alcohols was developed. The method is based on cycloalumination of olefins with trialkylalanes in the presence of Zr-containing catalysts followed by the CuCl-catalyzed in situ reaction of the corresponding aluminacyclopentanes with aldehydes or ketones. 相似文献
10.
The proper time method is used to examine the effect of polarization of the electron-positron vacuum on the nature of the interaction of a charged particle with the field of a nucleus and a magnetic field. It is shown that the interaction of an electron with a nucleus becomes anisotropic in the presence of a magnetic field. The dielectric constants of the vacuum and the effective charge of the Coulomb center are calculated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 38–45, November, 1986. 相似文献