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31.
32.
Yu. V. Nelyubina G. A. Gazieva V. V. Baranov P. A. Belyakov A. O. Chizhov K. A. Lyssenko A. N. Kravchenko 《Russian Chemical Bulletin》2009,58(7):1353-1360
1,3-H2-, 1,3-Me2-, and 1,3-Et2-4,5-Dihydroxyimidazolidine-2-thiones were synthesized and their structural peculiarities were studied. A comparative analysis
of dihydroxyimidazolidine-2-thione and its carbonyl analog performed in the framework of detailed investigation of the electron
density distribution in the corresponding crystals revealed the reason for different number and geometric parameters of the
hydrogen bonds formed by the (thio)carbonyl groups in the crystals. 相似文献
33.
34.
Tavtorkin A. N. Sviridova L. A. Golubeva G. A. Nelyubina Yu. V. Lyssenko K. A. Kochetkov K. A. 《Russian Chemical Bulletin》2009,58(3):624-630
The conditions were found for the diastereoselective reduction of racemic ketones of the pyrazolidine series to alcohols.
The latter compounds were preparatively isolated and characterized. The reduction of ketones with sodium borohydride on the
surface of an adsorbent without a solvent affords predominantly one group of diastereomers, whereas the reduction with lithium
tri-tert-butoxyaluminohydride in solution gives rise to another group of diastereomers. 相似文献
35.
A. Klochikhin S. G. Ogloblin S. Permogorov A. Reznitsky C. Klingshirn V. Lyssenko J. M. Hvam 《JETP Letters》2000,72(6):320-323
It is shown that the integrated luminescence intensity of localized excitons in solid solutions ZnSe(1?c)Tec has a component slowly decaying with time. After the excitation above the mobility threshold, the long-time intensity decreases exponentially, with a fractional exponent changing from a value corresponding to the critical index of anomalous diffusion to the index of normal diffusion as the temperature increases from 5 to 80 K. This change allows estimation of the energy scale for the fluctuation tail of the conduction band. 相似文献
36.
Detailed study of the crystal packing of 8,9,10,12-tetrafluoro-o-carborane by the topological analysis of the electron density distribution function was performed and the competing between
the F...H and H...H interactions in the crystal was investigated. 相似文献
37.
O. V. Bykhovskaya I. M. Aladzheva D. I. Lobanov P. V. Petrovskii K. A. Lyssenko I. V. Fedyanin T. A. Mastryukova 《Russian Chemical Bulletin》2005,54(11):2642-2647
2-Oxo-1,2-azaphospholanes and 1,2-azaphospholanium salts containing an amino acid fragment were synthesized by intramolecular
P-alkylation of N-3-chloropropyl-substituted tricoordinate phosphorus amides. Hydrolysis of 2-oxo-1,2-azaphospholanes at the P-N bond gives
rise to γ-aminopropylphosphonic acid derivatives.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2557–2562, November, 2005. 相似文献
38.
Experimental Charge Density Evidence for Pnicogen Bonding in a Crystal of Ammonium Chloride
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Dr. Yulia V. Nelyubina Prof. Alexander A. Korlyukov Prof. Konstantin A. Lyssenko 《Chemphyschem》2015,16(3):676-681
Chemical binding in crystalline ammonium chloride, a simple inorganic salt with an unexpectedly complex bonding pattern, was studied by using a topological analysis of electron density function derived from high‐resolution X‐ray diffraction. Supported by periodic quantum chemical calculations, it provided experimental evidence for weak σ‐hole bonds (1.5 kcal mol?1) that involve ammonium cations in a crystal. Our results show this type of supramolecular interaction to be more numerous than has been found to date by using gas‐phase calculations or statistical analysis of CSD. 相似文献
39.
S.?N.?Melnikov K.?A.?Lyssenko I.?V.?AnanyevEmail author I.?L.?Eremenko 《Russian Chemical Bulletin》2017,66(9):1550-1556
The results of geometric analysis of 588 crystal structures of square-planar nickel complexes containing short intermolecular Ni…X contacts (X is a non-metal atom) are reported. The frequency of occurrence of Ni…X interactions of a particular type was evaluated depending on the nature of the X atom and geometric characteristics. The promolecular functions RDG and sign(λ2)?ρ(r) were used to analyze the character of Ni…X interactions in attractive/repulsive terms. The relative strength of these interactions was determined as the function of the nature of the X atom and the direction of charge transfer. 相似文献
40.
V. Yu. Rad��kov G. G. Skvortsov G. K. Fukin K. A. Lyssenko M. Yu. Antipin A. A. Trifonov 《Russian Chemical Bulletin》2011,60(5):803-808
The reaction of lithium silylamide [??o-MeOC6H4N(SiMe3)}Li(OEt2)]2 with 2 equiv. of benzonitrile in THF at ??20 °C affords the lithium derivative of the new tridentate amidinate ligand [{o-MeOC6H4NC(Ph)N(SiMe3)}Li]2. The X-ray diffraction study showed that this complex has a dimeric structure due to the coordination of the N atoms and the ether group of one amidinate ligand to different Li atoms. The reaction of anhydrous YCl3 with the resulting complex in THF gives the monoamidinate complex [{o-MeOC6H4NC(Ph)N(SiMe3)}YCl2(THF)2]2 regardless of the reagent ratio. The latter has a dimeric structure in the crystalline state as a result of the presence of two ??2-bridging Cl atoms that link Y atoms. The ether groups of the amidinate ligands are not involved in the metal-ligand interaction. 相似文献