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71.
V. A. Chornous A. M. Grozav E. B. Rusanov A. M. Nesterenko M. V. Vovk 《Russian Journal of Organic Chemistry》2011,47(5):702-709
1-Alkyl(aryl)imidazolidine-2,4-diones reacted with Vilsmeier-Haack reagent affording 1-alkyl(aryl)-2,4-dichloro-1H-imidazole-5-carbaldehydes whose reactions with sodium azide, sodium alkoholates, with phenols, thiols, and secondary cycloalkylamines
led to the substitution of chlorine in the position 2 of the imidazole ring. The reaction with primary amines resulted in the condensation products at the aldehyde group. 相似文献
72.
A. I. Vas’kevich N. M. Tsizorik E. B. Rusanov V. I. Stanitets M. V. Vovk 《Russian Journal of Organic Chemistry》2011,47(8):1146-1152
Sterically nonhindered N-alkyl(aryl)amides of cinnamylacetic acid in the reaction with phenyl(4-tolyl)sulfenyl chlorides in
acetic acid in the presence of lithium perchlorate undergo a selective cyclization into 5-arylsulfanyl-6-phenylpiperidin-2-ones.
Under similar conditions the reaction with arylsulfenyl chlorides of amides containing bulky substituents at the nitrogen
atom resulted in 5-arylsulfanyl-6-phenyltetrahydropyran-2-iminium perchlorates, which by treatment with aqueous ethanol were
converted into the corresponding derivatives of pyran-2-ones. 相似文献
73.
A. V. Bentya R. I. Vas’kevich A. V. Turov E. B. Rusanov M. V. Vovk V. I. Staninets 《Russian Journal of Organic Chemistry》2011,47(7):1066-1073
6-Allyl(diallyl, prop-2-yn-1-yl)amino-1-R-pyrazolo[3,4-d]pyrimidin-4(5H)-ones reacted with iodine to give angularly fused 8-iodomethyl-7,8-dihydro-1-R-imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(6H)-ones which were treated with sodium acetate to obtain 8-methylidene-1-R-7,8-dihydroimidazo[1,2-a]pyrazolo-[4,3-e]pyrimidin-4(6H)-ones as a result of elimination of hydrogen iodide. 8-Methylidene-1-R-7,8-dihydroimidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(6H)-ones were converted into 8-methyl-1-R-imidazo[1,2-a]pyrazolo-[4,3-e]pyrimidin-4(5H)-ones on heating to the melting point. 8-Methylidene-1-phenyl-7,8-dihydroimidazo-[1,2-a]pyrazolo[4,3-e]pyrimidin-4(6H)-one underwent isomerization into linearly fused 6-methyl-1-phenyl-1,8-dihydro-4H-imidazo[1,2-a]pyrazolo[3,4-d]pyrimidin-4-one on heating in sulfuric acid. 相似文献
74.
In contrast to the thermodynamics of fluid surfaces, the thermodynamics of solid surfaces was not elaborated in detail by Gibbs and other founders of surface thermodynamics. During recent decades, significant progress in this field has been achieved in both the understanding of old notions, like chemical potentials, and in formulating new areas. Applying to solid surfaces, basic relationships of classical theory of capillarity, such as the Laplace equation, the Young equation, the Gibbs adsorption equation, the Gibbs-Curie principle, the Wulff theorem and the Dupré rule, were reformulated and generalized. The thermodynamics of self-dispersion of solids and the thermodynamics of contact line phenomena were developed as well. This review provides a fresh insight into the modern state of the thermodynamics of solid surfaces. Not only a solid surface itself, both in a macroscopic body and in the system of fine particles, but also the interaction of solid surfaces with fluid phases, such as wetting phenomenon, will be analyzed. As the development of surface thermodynamics has given a powerful impetus to the creation of new experimental methods, some of these will be described as examples. 相似文献
75.
The specific features of the luminescence of excimer molecules are analyzed within the model of a purely repulsive potential for the ground state in the field of intense laser radiation with due regard for the squeezed vibrational states. It is demonstrated that the luminescence band with the inclusion of the equilibrium phonons can be represented by a broad structureless asymmetric bell-shaped curve. The squeezed vibrational states substantially affect the frequency dependence of the luminescence intensity; more specifically, the luminescence band exhibits two maxima in the case of strong electron-phonon coupling. The stabilization of an excited electronic state in the course of luminescence at the fundamental frequency and generation of higher optical harmonics in the field of intense laser radiation is discussed. 相似文献
76.
Lyudmila F. Lourie Galina V. Shevchenko Alexander N. Chernega Eduard B. Rusanov Judith A.K. Howard 《Journal of fluorine chemistry》2006,127(3):377-385
The selective fluorolactonization was achieved by treatment of cis-5-norbornene-2,3-endo-dicarboxylic acid or its monomethyl and dimethyl esters with F-TEDA-BF4 or XeF2. The reactions of 5-norbornene-endo-2-carboxylic acid and its monomethyl ester with F-TEDA-BF4 or XeF2 proceed in a non-selective manner to give fluorolactonization, addition and rearrangement products. The basic factor responsible for selectivity of the fluorolactonization is the presence of two endo-oriented carboxyl groups in the substrate molecule. The electrophilicity and type of the fluorinating agent is of secondary importance in this regard. It is postulated that the fluorolactonization of norbornenecarboxylic acids and their methyl esters with F-TEDA-BF4 or XeF2 is realized mainly via “open” fluoronorbornyl carbocation intermediates which in the reaction with XeF2 are postulated as the tight ion pairs. 相似文献
77.
The condition of internal mechanical equilibrium of a curved surface layer is derived, and its application to practically important cases of incomplete formation of the surface layer (as is sometimes the case, for example, in thin films) is considered. The notion of a local disjoining pressure is introduced, and the equilibrium condition for a variable-thickness thin film is obtained; this condition is valid both in the absence and in the presence of external fields. The cases of a wedge-shaped film, cylindrical film, spherical film, and transition zone of a wetting film are analyzed.__________Translated from Kolloidnyi Zhurnal, Vol. 67, No. 2, 2005, pp. 235–242.Original Russian Text Copyright © 2005 by Rusanov, Shchekin. 相似文献
78.
79.