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111.
4-(2-Chlorophenyl)-3-cyano-6-hydroxy-5-(2-thienoyl)-6-trifluoromethylpiperidin-2-thione, which was used for the synthesis of 2-allylthio-4-(2-chlorophenyl)-3-cyano-6-hydroxy-5-(2-thienoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine, was obtained by the reaction of 2-thienoyltrifluoroacetone with 2-chlorophenylphenylmethylenecyanothioacetamide or with a mixture of 2-chlorobenzaldehyde and cyanothioacetamide in the presence of N-methylmorpholine. The molecular and crystal structure of the piperidinthione have been established by X-ray crystallography.  相似文献   
112.
Chemistry of Heterocyclic Compounds - Intramolecular halocyclization of N-allyl-4,5-dihydro-3H-1-benzazepin-2-amines, obtained by consecutive methylation and allylamination of benzazepin-2-ones, by...  相似文献   
113.
Reactions of new bis(α-diketones) with 1,3-diphenylacetone resulted in new bis(tetraarylcyclopentadienones).  相似文献   
114.
115.
The theory of transverse elasticity of thin foam films is formulated under the conditions when the action of Gibbs elasticity is excluded. The theory predicts the presence of maxima of the modulus of transverse elasticity and film thickness near the critical micellization concentration as functions of the content of surfactant at a given disjoining pressure. Theoretical conclusions are confirmed experimentally by measuring film thickness at various heights of equilibrium foam column.  相似文献   
116.
A methodological supplement has been proposed to author previous paper on the correlation between the mobility and diffusion coefficient (Colloid J., 2016, vol. 78, p. 88). Now, the self-diffusion coefficient has been added to the aforementioned parameters. It has been found when it coincides with the diffusion coefficient and when not. The correlation between the three transport properties has been established, and appropriate schemes of their experimental study have been considered. The computational relations based on the traditional assumption of constant aggregation numbers have been generalized taking into account recent results of studying the effect of variability of surfactant aggregation numbers.  相似文献   
117.
Dynamic light scattering, conductometry, and capillary viscometry have been used to study aqueous micellar solutions of dodecyl-, tetradecyl-, and hexadecyltriphenylphosphonium bromides in a wide range of concentrations covering the first and second critical micelle concentrations (CMC1 and CMC2). It has been shown that the concentration curves for the diffusion coefficients of the ionic surfactants increase above CMC1 and, then, pass through a maximum. As the alkyl chain length increases, the slopes of the concentration curves within the range of the linear growth in the diffusion coefficient rise, the height of the maximum increases, and its position shifts toward lower concentrations. The obtained results have been explained in terms of a theory previously developed for ideal micellar systems. It has been shown that the mobility factor plays the predominant role in the range of the linear increase in the diffusion coefficient and the effect of the viscosity of a micellar surfactant solution is enhanced with a rise in its concentration.  相似文献   
118.
Investigations on separating hydrogen isotopes have been carried out in a system with plasma rotating in crossed E × B fields— a plasma centrifuge. The processing of chemical reactions in the plasma phase in a strong centrifugal field was simulated. High radial separation factors (up to 140) have been obtained for the decomposition of water vapor with simultaneous separation of hydrogen and oxygen. Because of spatial separation of the dissociation products there was no need for their special quenching.  相似文献   
119.
Michael reactions of isopropylidenemalononitrile with cyanothioacetamide (in the presence of 4-methoxyphenacyl bromide), cyclohexane-1,3-dione, and 4-hydroxycoumarin, gave 6-amino-2-(4-methoxy-benzoylmethylsulfanyl)-4,4-dimethyl-1,4-dihydropyridine-3,5-dicarbonitrile, 2-amino-4,4-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile, and 2-amino-4,4-dimethyl-5-oxo-4H,5H-pyrano[3,2-c]-chromene-3-carbonitrile, respectively. In the reaction of isopropylidenemalononitrile with cyanoacetamide, only dimerization product of the former, 2-amino-4,6,6-trimethylcyclohexa-2,4-diene-1,1,3-tricarbonitrile, was isolated. Its structure was proved by X-ray analysis.  相似文献   
120.
The interaction of N-methylmorpholinium 1-amino-2,4-dicyano-4-ethoxycarbonyl-1,3-butadienethiolate with primary amines and formaldehyde leads to the formation of ethyl esters of 7-cyano-6-thioxo-1,3,4,6-2H-pyrido[1,2-a][1,3,5]triazine-9-carboxylic acid in place of the expected derivatives of pyrido[2,1-b][1,3,5]thiadiazine. The structure of the ethyl ester of 7-cyano-3-phenyl-6-thioxo-1,3,4,6-2H-pyrido[1,2-a][1,3,5]triazine-9-carboxylic acid was demonstrated by X-ray structural analysis. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1075–1081, July, 2007.  相似文献   
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