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41.
Kazheva O. N. Aleksandrov G. G. D'yachenko O. A. Chernov'yants M. S. Lykova E. O. Tolpygin I. E. Raskita I. M. 《Russian Journal of Coordination Chemistry》2004,30(8):599-603
Complexation in the N-ethylquinolinium iodide–molecular iodine system in a chloroform solution is studied. The stability constant of N-ethylquinolinium triiodide (I) is determined by spectrophotometric methods of stoichiometric dilution using the average iodine number function. Compound I with the [C9H7NC2H5]I3 composition is studied by X-ray diffraction analysis. The crystal structure is formed by alternating layers of cations arranged by the ladder type and triiodide anions with equalized interatomic distances. The triiodide anions are linked to form chains through strongly shortened intermolecular contacts. 相似文献
42.
Pozharskii AF Ryabtsova OV Ozeryanskii VA Degtyarev AV Kazheva ON Alexandrov GG Dyachenko OA 《The Journal of organic chemistry》2003,68(26):10109-10122
On treatment of 2,7-dilithio- (6a) and 2,7-bis(bromomagnesio)- (6b) naphthalenes with a number of electrophiles, new "proton sponge" derivatives 7a-e,g, containing iodo, methylthio, trimethylsilyl, methyl, n-butyl, and ethoxycarbonyl groups in ortho-positions to dimethylamino groups, have been synthesized. The investigation of their molecular structure, spectral characteristics, and basicity reveals that the latter is mainly determined by two groups of factors: (1) the polar effect of ortho-substituents and (2) the so-called "buttressing effect" representing the complex combination of various sterical interactions of ortho-substituents with dimethylamino groups in corresponding bases and cations. A contradictory directionality of these interactions strongly reduces the importance of the buttressing effect in the case of compounds with bulky ortho-substituents, which is most clearly displayed in the absence of any relationship between the size of ortho-substituents and the basicity. On the contrary, for proton sponges having in ortho-positions the electron-donating groups with lesser steric demands, both the buttressing and the polar effects act in the same direction. This is the reason for the exceptionally high basicity of 2,7-dimethoxy- (2) and tetrakis(dimethylamino)- (3a) naphthalenes. It has been found that bis(trimethylsilyl)-bis(dimethylamino)naphthalene 7d has an in-out configuration of the NMe2 groups in the solid that is the first example of its kind in the series of naphthalene proton sponges. The origin of a yellow coloring of 2,7-disubstituted proton sponges is also discussed. 相似文献
43.
Kazheva O. N. D'yachenko O. A. Chernov'yants M. S. Gol'eva V. E. Pyshchev A. I. 《Russian Journal of General Chemistry》2002,72(10):1521-1524
The complex formation in the system bis[2-(trimethylammonio)ethyl] succinate diodide-iodine involves no more than two iodine molecules. The crystal structure of the salt [(CH3)3N(CH2)2OCOCH2]2(I3)2 is formed by layers of inorganic anions (I3
-) and organic dications (centrosymmetric dications {[(CH3)3N · (CH2)2OCOCH2]+}2), evenly alternating along the a axis. The crystal structure of the salt [(CH3)3N(CH2)2·OCOCH2]2(I3)2(I2)0.5 is formed by organic and inorganic layers evenly alternating along the [011] diagonal, with a centrosymmetric iodine molecule. 相似文献
44.
M. V. Pryadeina Ya. V. Burgart V. I. Saloutin P. A. Slepukhin O. N. Kazheva G. V. Shilov O. A. D’yachenko O. N. Chupakhin 《Russian Journal of Organic Chemistry》2007,43(7):945-955
Condensation of ethyl 3-polyfluoroalkyl-3-oxopropionates with excess triethyl orthoformate gave ethyl 3-polyfluoroalkyl-2-ethoxymethylidene-3-oxopropionates which reacted with primary aliphatic, aromatic, and heterocyclic amines to form ethyl 2-alkyl(aryl, hetaryl)aminomethylidene-3-polyfluoroalkyl-3-oxopropionates. According to the X-ray diffraction and IR data, the latter exist in the crystalline state as the corresponding E isomers, while in solution (NMR data), as mixtures of Z and E isomers. Condensation of ethyl 2-ethoxymethylidene-3-oxopropionates with secondary heterocyclic amines (morpholine and pyrrolidine) led to the formation of 2-morpholino(pyrrolidin-1-yl)methylidene-3-fluoroalkyl-3-oxopropionates which were shown to exist as Z isomers both in the crystalline state and in solution. 相似文献
45.
G. Novitski A. Borta S. Shova O. N. Kazheva M. Gdaniec Yu. A. Simonov 《Russian Journal of Inorganic Chemistry》2008,53(2):202-208
The Co(III) complexes with pyridinecarboxylic acid, Na[Co(Pc)2(NO2)2] (I) and NH4[Co(Pc)2(NO2)2] (II), where Pc is the 2-pyridinecarboxylate anion, have been synthesized and studied by X-ray diffraction. In the crystal, the complex anions are combined through the Na+ and NH 4 + cations. In II, the anion and the cation are combined by hydrogen bonds. 相似文献
46.
Alexander V. Artem’ev Nina K. Gusarova Svetlana F. Malysheva Olga N. Kazheva Grigorii G. Alexandrov Oleg A. Dyachenko Boris A. Trofimov 《Mendeleev Communications》2012,22(6):294-296
The first europium(iii) pyridylphosphine complex, [Eu(N,N’,N”-2-Py3P)(NO3)3] was prepared by the reaction between Eu(NO3)3.6H2O and tris(2-pyridyl)phosphine; its structure was characterized by single-crystal X-ray diffraction. 相似文献
47.
Tatyana E. Glotova Igor A. Ushakov Olga N. Kazheva Oleg A. Dyachenko Boris A. Trofimov 《Tetrahedron》2009,65(47):9814-188
The one-pot reaction of natural amino acids (glycine, β-alanine, γ-aminobutyric and ?-aminocapronic acids, d,l-valine, d,l-leucine, anthranilic acid) with bielectrophilic acylacetylenes proceeds chemo-, regio- and stereospecifically in the presence of NaOH (45-50 °C, 4 h, EtOH-H2O) to give (after treatment of the reaction mixture with aqueous HCl) Z-isomers of N-acylvinyl derivatives of amino acids in 87-94% yield. 相似文献
48.
Boris A. Trofimov Olga V. Petrova Vladislav N. Drichkov Igor' A. Ushakov Olga N. Kazheva Anatolii N. Chekhlov Oleg A. Dyachenko 《Tetrahedron》2006,62(17):4146-4152
2-(2-Cyano-1-ethylthioethenyl)pyrroles easy exchange their ethylthio group for hydroxyl (NaOH, H2O-methanol, 40-45 °C, 1 h) to give 2-(2-cyano-1-hydroxyethenyl)pyrroles, a new family of stable enols, in 50-94% yields. The vinylic nucleophilic substitution proceeds at the double bond of both the starting pyrroles and their cyclic isomers, 3-iminopyrrolizines. X-ray structure analysis and NMR spectra show the enols to be stabilized by exceptionally strong intramolecular H-bonding. 相似文献
49.
O. G. Khudina E. V. Shchegol’kov Ya. V. Burgart M. I. Kodess V. I. Saloutin O. N. Kazheva G. V. Shilov O. A. D’yachenko M. A. Grishina V. A. Potemkin O. N. Chupakhin 《Russian Journal of Organic Chemistry》2007,43(3):380-387
According to the 1H, 13C, and 19F NMR data, fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones in CDCl3 exist exclusively, while in (CD3)2CO preferentially, as isomers in which the acyl or aroyl group is involved in intramolecular hydrogen bond. The isomer structure was assigned on the basis of the chemical shifts of the carbonyl carbon atoms and fluorine atoms and carbon-fluorine spin-spin coupling constants J C-F. X-Ray diffraction data showed that 1,2,3-trione 2-arylhydrazones in crystal have the same structure as in CDCl3 solution. Quantum-chemical calculations were performed to rationalize predominant formation of 1,2,3-trione 2-arylhydrazone isomers with a free polyfluoroacyl group. 相似文献
50.
Boris A. Trofimov Anastasiya G. Mal’kina Valentina V. Nosyreva Olga N. Kazheva Oleg A. Dyachenko 《Tetrahedron letters》2008,49(19):3104-3107
The reaction of α,β-acetylenic γ-hydroxy nitriles with thiosemicarbazide, under mild conditions (rt, no catalyst, in 1:1 aqueous ethanol, 4-14 h), proceeds chemo-, regio- and stereoselectively to give atypically so far inaccessible tri-functionalized (amino, hydroxyl and thioamide groups) pyrazoles in 53-91% yields. The hydroxyl function is easily protected by using the corresponding acetals of the starting acetylenic hydroxy nitriles. 相似文献