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This paper studies the crystal structure of new substituted light-sensitive azomethine N-oxides (nitrones): C-2′-(o-oxyphenyl)vinyl-N-p-methylphenyl
nitrone (1), C-2′-(2″-oxy-5″-bromophenyl)vinyl-N-p-methylphenyl nitrone (2), C-2′-(2″-oxy-5″-bromophenyl)-vinyl-N-phenyl nitrone
(3), and C-2′-(o-oxyphenyl)vinyl-N-methyl nitrone (4). In contrast to the compounds studied earlier [1, 2], C-2′-(β-oxy-α-naphthyl)vinyl-N-p-methylphenyl
nitrone (5), C-2′-(β-oxy-α-naphthyl)vinyl-N-phenyl nitrone (6), C-2′-(o-oxyphenyl) vinyl-N-phenyl nitrone (7), and C-2′-(o-oxyphenyl)vinyl-N-p-bromophenyl
nitrone (8), the nitrones studies in this work have anti-rather than syn-orientations of the nitrone and hydroxyl groups.
Due to this spatial arrangement of the proton-donating hydroxyl and proton-accepting nitrone groups, molecules in crystals
1–4 are bonded by intermolecular hydrogen bonds (IHB) to form chains but not centrosymmetric dimeric associates (CDA). Two
types of chain arrangements were revealed: “head-to-tail” and “head-to-tail, tail-to-head”. It is shown that the introduction
of an alkyl substituent instead of an aryl one at the nitrogen atom of the nitrone group in 4 leads to a change in the geometry
of the IHB in the H-associate. It is proven that the hydroxyl proton can undergo an intermolecular O→O transfer in the chain
of hydrogen bonds in crystals 1–4, which can give rise to photochemical transformations in these crystals.
Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 2, pp. 349–362, March–April, 1996.
Translated by L. Smolina 相似文献
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I. I. Chuev S. M. Aldoshin E. G. Atovmyan D. B. Frolov A. N. Utenyshev 《Russian Chemical Bulletin》1996,45(4):851-855
N-Thenylidene- andN-(o-nitrobenzylidene)hydrazides of isonicotinic acid have been studied by X-ray structural analysis and IR spectroscopy. In the crystalline state, these molecules are linked through intermolecular N—H ... Npy hydrogen bonds. Carbonyl groups are not involved in intermolecular hydrogen bonds. However, it was found that the C=O group participates in an attractive interaction with the sulfur atom of the thiophene group. The energy of this interaction is comparable with the energies of intermolecular C=O ... H—N hydrogen bonds in amides.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 896–900, April, 1996. 相似文献
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K. V. Bozhenko S. M. Aldoshin V. I. Minkin A. D. Garnovskii I. S. Vasilchenko A. N. Utenyshev A. A. Khrulev 《Russian Chemical Bulletin》2010,59(3):489-496
B3LYP/LANL2DZ calculations of two series of isomeric dinuclear copper chelates based on the tridentate dibasic salicylaldimines
from aromatic and heterocyclic amines were performed. According to calculations, the complexes with N,N-or S,S-donor atoms
in the exchange fragment are mainly characterized by ferromagnetic exchange, whereas the formation of O, O-bridging fragments
leads to antiferromagnetic spin-spin interaction. 相似文献
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S. M. Aldoshin V. V. Tkachev K. N. Khalanskii B. S. Lukyanov V. I. Minkin A. N. Utenyshev Yu. S. Alekseenko S. O. Bezuglyi 《Russian Chemical Bulletin》2011,60(7):1380-1383
A new photochromic spiropyran of the benzoindoline series containing the quinoline moiety was synthesized. Its structure was
determined by IR and 1H NMR spectroscopy. The crystal structure of the new compound was established by X-ray diffraction. The photochromic properties
of the synthesized spiropyran were investigated. 相似文献
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G. L. Gutsev K. V. Bozhenko L. G. Gutsev A. N. Utenyshev S. M. Aldoshin 《Journal of computational chemistry》2019,40(3):562-571
The geometrical structures and properties of the M8O12, M8O12H8, and M8O12H12 clusters are explored using density functional theory with the generalized gradient approximation for all 3d-metals M from Sc to Zn. It is found that the geometries and total spin magnetic moments of the clusters depended strongly on the 3d-atom type and the hydrogenation extent. More than the half of all of the 30 clusters had singlet lowest total energy states, which could be described as either nonmagnetic or antiferromagnetic. Hydrogenation increases the total spin magnetic moments of the M8O12H12 clusters when MMn Ni, which become larger by four Bohr magneton than those of the corresponding unary clusters M8. Hydrogenation substantially affects such properties as polarizability, forbidden band gaps, and dipole moments. Collective superexchange where the local total spin magnetic moments of two atom squads are coupled antiparallel was observed in antiferromagnetic singlet states of Fe8O12H8 and Co8O12H8, whereas the lowest total energy states of their neighbors Mn8O12H8 and Ni8O12H8 are ferrimagnetic and ferromagnetic, respectively. Hydrogenation leads to a decrease in the average binding energy per atom when moving across the 3d-metal atom series. © 2018 Wiley Periodicals, Inc. 相似文献
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B. S. Lukyanov A. N. Utenyshev V. V. Tkachev S. M. Aldoshin V. I. Minkin M. B. Lukyanova Yu. S. Alekseenko 《Chemistry of Heterocyclic Compounds》2008,44(2):163-169
The structure of an indoline spiropyran of molecular formula C29H33NO2 has been studied by X-ray crystallographic analysis. Structural parameters have been determined for this spiropyran, containing
a condensed furan fragment with a tert-butyl group, in comparison with the structure of other spiropyrans of this series.
The observation in the absorption spectrum of a photoinduced cis-cis isomer is linked with its stabilization by the steric
effect of the bulky tert-butyl group and the strength of barriers at 77 K.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 221–228, February, 2008. 相似文献
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O. S. Popova V. A. Bren’ V. V. Tkachev A. N. Utenyshev Yu. V. Revinskii K. S. Tikhomirova V. P. Rybalkin A. G. Starikov G. S. Borodkin A. D. Dubonosov G. V. Shilov S. M. Aldoshin V. I. Minkin 《Doklady Chemistry》2016,471(1):311-313
Potentially tautomeric azomethine imine, 1-[(3-hydroxybenzo[b]thiophen-2-yl)methylidene]-3-oxo-5-phenyl-1-pyrazolidinium-2-ide has been prepared. According to X-ray diffraction, 1H, 13C, and 15N NMR and electronic spectroscopy, the compound exists as 3-hydroxybenzothiophene structure containing intermolecular hydrogen bond between the hydroxy group and the carbonyl oxygen of the pyrazolidone ring in crystal state. Quantum chemical calculations predict the possibility of OH and NH tautomeric forms. 相似文献
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S. M. Aldoshin I. I. Chuev O. S. Filipenko A. N. Utenyshev G. Harie V. Lokshin A. Samat R. Guglielmetti G. Pepe 《Russian Chemical Bulletin》1998,47(6):1098-1104
Three 2,2-diaryl-substituted pyridoannelated [2H]-chromenes have been studied by X-ray diffraction analysis. Bonding of the benzene rings through bridges of different nature
and with different length affects substantially the orientation of the benzene rings, steric interactions at the C center,
the conformation of the molecule, and the C−O bond length. A correlation between the photocolorability of chromenes under
study and the orientation of the benzene rings with respect to the C−O bond, which provides different prerequisites to stabilization
of the C(1)-centered, cation formed upon cleavage of the C−O bond, was established. The effect of the orientation of the benzene
rings on the dark reaction of ring closure was found.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1129–1135, June, 1998. 相似文献