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11.
We construct an infinite set of new types of -fibered Fitting classes of finite groups that differ from -local classes. We also describe the structure of maximal inner -satellites for the main types and establish a relationship between -fibered and -foliated Fitting classes. 相似文献
12.
The ligand tripyridinedimethane (tpdm), consisting of three pyridine residues linked at their ortho carbons by two CH(2) groups, is shown to be a sterically flexible ligand capable of binding in a meridional arrangement in trigonal bipyramidal (tpdm) Cu(II)Cl(2) but binding in a facial arrangement in tetrahedral (tpdm) Cu(I)Cl. Nucleophilic substitution of chloride by (t)BuO(-) and PhC[triple bond]C(-) is possible, and deprotonation of the acidic benzylic protons does not take place because the resulting carbanion cannot achieve coplanarity with the aryl rings. RhCl(3) forms, with tpdm in boiling methanol, a 1:1 kinetic mixture of fac- and mer-isomers RhCl(3)(tpdm). The former isomerizes slowly at RT (room temperature) in DMSO solution into the latter with Rh-N bond dissociation as the rate-determining step. 相似文献
13.
Marchenko AV Vedernikov AN Dye DF Pink M Zaleski JM Caulton KG 《Inorganic chemistry》2004,43(1):351-360
The reaction of equimolar NO with the 16 electron molecule RuHCl(CO)L(2) (L = P(i)Pr(3)) proceeds, via a radical adduct RuHCl(CO)(NO) L(2), onward to form RuCl(NO)(CO)L(2) (X-ray structure determination) and RuHCl(HNO)(CO)L(2), in a 1:1 mole ratio. The HNO ligand, bound by N and trans to hydride, is rapidly degraded by excess NO. The osmium complex behaves analogously, but the adduct has a higher formation constant, permitting determination of its IR spectrum; both MHCl(CO)(NO)L(2) radicals are characterized by EPR spectroscopy, and DFT calculations on the Ru system show it to have a "half-bent" Ru-N-O unit with the spin density mainly on nitrogen. DFT (PBE) energies rule out certain possible mechanistic steps for forming the two products. A survey of the literature leads to the hypothesis that NO should generally be considered as a (neutral) Lewis base (2-electron donor) when it binds to a 16 electron complex which is resistant to oxidation or reduction, and that the resulting N-centered radical has a M-N-O angle of approximately 140 degrees, which distinguishes it from NO(-) (bent at <140 degrees ) and from NO(+) (>170 degrees ). 相似文献
14.
15.
S. P. Gromov E. N. Ushakov A. I. Vedernikov L. G. Kuz’mina M. V. Alfimov 《Theoretical and Experimental Chemistry》2009,45(1):3-11
A universal approach to the molecular design of light-sensitive nanodimensional systems with specific characteristics was
developed on the basis of unsaturated and macrocyclic compounds. It was possible to construct various nanodimensional systems
within the scope of a single class of compound using a limited number of components. The use of photostructural transformations
to control complex formation and mechanical movements in molecular devices and machines is discussed.
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 45, No. 1, pp. 1–7, January-February, 2009. 相似文献
16.
This survey is a continuation of the survey published in the Problems of Geometry Series, Vol. 15. It consists of an exposition of the general theory of homogeneous spaces defined by prescribing a set of endomorphisms of a Lie groupG. The morphisms of the homogeneous spaces so constructed are built up in the standard way and the geometry generated by these morphisms is studied.Translated from Itogi Nauki i Tekhniki, Seriya Problemy Geometrii, Vol. 19, pp. 155–185, 1987. 相似文献
17.
Humulene and its derivatives (6R)-hydroxy-α-humulene [(6R)-hydroxy-(1E,4E,8E)-4,8,11,11tetramethylcycloundeca-1,4,8-triene], (6R)-acetoxy-α-humulene [(6R)-acetoxy-(1E,4E,8E)-4,8,11,11tetramethylcycloundeca-1,4,8-triene], a coumaric acid ester, 14-hydroxy-α-humulene [14-coumaroxy(1E,4E,8E)-4,8,11,11-tetramethylcycloundeca-1,4,8-triene], (1E,6R,8E)-4,5-epoxy-6-hydroxy-4,8,11,11tetramethylcycloundeca-1,8-diene, and (6R,9S)-4,11,11-trimethyl-8-methylene-1,4-cycloundecadien-6,9-diol were observed in the hydrocarbon extract of Betula pendula (Betulaceae) buds. The GC retention indices were determined for all identified compounds. 相似文献
18.
A. I. Vedernikov S. S. Basok S. P. Gromov L. G. Kuz’mina V. G. Avakyan N. A. Lobova E. Yu. Kulygina T. V. Titkov Yu. A. Strelenko E. I. Ivanov J. A. K. Howard M. V. Alfimov 《Russian Journal of Organic Chemistry》2005,41(6):843-854
An improved procedure was proposed for the synthesis of stilbenes fused to two crown ether fragments at both benzene rings. The structure of new homologous symmetric bis-crown-containing stilbenes was determined by X-ray analysis. Relations were revealed between the size of the crown ether moiety and stilbene conformation in crystal and the mode of crystal packing. Conformational analysis of the prepared stilbenes in solution and in the solid state was performed by 1H and 13C NMR spectroscopy and by DFT quantum-chemical calculations.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 864–875.Original Russian Text Copyright © 2005 by Vedernikov, Basok, Gromov, Kuz’mina, Avakyan, Lobova, Kulygina, Titkov, Strelenko, Ivanov, Howard, Alfimov. 相似文献
19.
S. P. Gromov O. A. Fedorova A. L. Vedernikov V. V. Samoshin M. V. Alfimov 《Russian Chemical Bulletin》1993,42(5):960-961
Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, p. 996, May, 1993. 相似文献
20.