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21.
22.
V. K. Turchaninov D. K. Danovich A. F. Ermikov M. A. Andriyankov 《Russian Chemical Bulletin》1992,41(4):678-683
Analysis of the orbital structure of isomeric pyridines carried out using photoelectron spectroscopy and the AM1 (GF) method showed that this structure is independent of the nature of the substituent at C
2(6)
and C
3(5)
: <n<. All the possible sequences of the highest occupied MO of different symmetry (, ) are realized for 4-substituted pyridines.For previous communication, see [1].Irkutsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk 664033. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 872–880, April, 1992. 相似文献
23.
V. K. Turchaninov A. I. Vokin D. -S. D. Toryashinova S. E. Korostova 《Russian Chemical Bulletin》1993,42(5):822-826
The characteristics of photoelectron (PE) spectra of 2-phenylpyrroles and biphenyls have been correlated with the UV spectroscopy data for their radical cations. The geometric and electronic structures of the compounds and radical cations have been calculated using the AM1 method. The absorption bands of the radical cations observed in the visible region of spectrum have been found to pertain to the quasi-Koopmans type,i.e., they are realized between the doubly and partially occupied -MO, but their energies differ strongly from those calculated on the basis of PE spectra. This is explained by the distinction between the spatial structure of a molecule and that of the respective radical cation. The second cause of the discrepancy between the data of the two spectral methods consists in orbital — interactions, which are most conspicuous in the case of 4(4)-halogen-substituted compounds.For Part 4 see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 869–874, May, 1993. 相似文献
24.
N. N. Chipanina L. V. Sherstyannikova I. V. Sterkhova V. K. Turchaninov B. A. Shainyan 《Russian Journal of General Chemistry》2005,75(2):268-271
The energy of formation of an open-chain N-methyltrifluoromethanesulfonamide dimer stabilized by the N-H⋯O=S hydrogen bond is 20.1 kJ mol−1 (CH2Cl2). This value exceeds by ∼12 kJ mol−1 the energy of formation of cyclic secondary methanesulfonamide self-associates per hydrogen bond.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 2, 2005, pp. 295–298.Original Russian Text Copyright © 2005 by Chipanina, Sherstyannikova, Sterkhova, Turchaninov, Shainyan. 相似文献
25.
Turchaninov V. K. Vokin A. I. Aksamentova T. N. Krivoruchka I. G. Shulunova A. M. Andriyankova L. V. 《Russian Journal of General Chemistry》2003,73(5):743-752
The effects of aprotic inert media on the electronic absorption spectra of aromatic nitro compounds p-NO2C6H4R were used as evidence for the linear correlation between the slope s
a of the solvatochromism equations max = 0 + s
a* and the dipole moments of the molecules in their ground electronic state g. A linear correlation was established between 0 and the first ionization potential of subunits C6H5R. A new approach to estimating the dipole moment of electronically excited molecules (e) for molecules like p-NO2C6H4R on the basis of the correlation e = rg was proposed. 相似文献
26.
K. B. Petrushenko V. K. Turchaninov A. I. Vokin A. F. Ermikov Yu. L. Frolov 《Chemistry of Heterocyclic Compounds》1985,21(6):626-628
The electron absorption spectra of the radical cations of indene heteroanalogs were studied by nanosecond laser photoexcitation. The absorption bands in the 450–650 nm region were assigned on the basis of absorption and photoelectron spectroscopy.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 750–752, June, 1985. 相似文献
27.
Voronkov M. G. Trofimova O. M. Turchaninov V. K. Zel'bst E. A. Bolgova Yu. I. Belyaeva V. V. Larina L. I. Aksamentova T. N. Mikhaleva A. I. Chernov N. F. 《Russian Journal of Organic Chemistry》2003,39(10):1458-1466
Organosilicon derivatives of pyrrole, indole, carbazole, and 2-methylindole containing (MeO)3SiCH2, Et3SiCH2, or N(CH2CH2O)3SiCH2 group on the nitrogen atom were synthesized. Their structure and stereoelectronic parameters were studied by X-ray diffraction, 1H, 1
3C, 1
5N, and 2
9Si NMR, IR and UV spectroscopy, and dielcometry, as well as by quantum-chemical calculations. 相似文献
28.
I. V. Sterkhova V. I. Mescheryakov N. N. Chipanina V. A. Kuhareva T. N. Aksamentova V. K. Turchaninov B. A. Shainyan 《Russian Journal of General Chemistry》2006,76(4):583-589
Bis(trifluoromethylsulfonylamino)methane in an inert medium exists as an equilibrium mixture of monomeric forms with various types of intramolecular hydrogen bonds, whose population depends on the polarity of the medium. The energetically most favorable form is a symmetrical form containing two N-H...O=S bonds. Less stable are the isomer with two N-H...F-C bonds and the unsymmetrical isomer with two different hydrogen bonds. N-[(Trifluoromethylsulfonyl)aminomethyl]acetamide contains one intramolecular intramolecular N-H...O=C hydrogen bond and preserves ability for self-association. 相似文献
29.
A correlation was found between the group dipole moments of substituents determined from the dipole moments of ethylene derivatives and the second ionization potentials of allene derivatives corresponding to the -MO of the C()-C() bond. It was shown that the concept of the effect of the substituent field cannot completely explain the observed phenomena, and the energies of the second ionic states of bromoallene and alkoxyallenes are lowered because of the interaction between nonbonded fragments through the systems of the compounds. It has been found that, in terms of orbital approximation, this interaction causes electronic destabilization of theanti-planar (trans) conformers of methoxyallene and methyl vinyl ether compared to theirsin-planar (cis) forms.For Part 5, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 48–54, January, 1995. 相似文献
30.
Turchaninov V. K. Murzina N. M. Vokin A. I. Trofimov B. A. 《Russian Journal of General Chemistry》2001,71(11):1701-1707
Rotational isomerism of 2-(tricyanovinyl)-5-phenylpyrrole and formation of complexes with a three-centered (bifurcational) hydrogen bond were studied by UV spectroscopy and quantum-chemical calculations. In the gas phase and in weakly and moderately protophilic media these compounds have mainly the syn-periplanar form stabilized by the intramolecular hydrogen bond involving the orthogonal system of the nitrile group and the NH hydrogen atom. No intermolecular H complex is formed in such solvents. In tetrahydrofuran, cyclohexanone, pyridine, and some other media a complex conformational equilibrium is observed. Interaction with aliphatic alcohols, amides, dimethyl sulfoxide, and triethylamine results in stabilization of the H complex of the anti-periplanar conformer. 相似文献