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In this paper we examine clathrate formation in the tetraisoamylammonium propionate-water binary system. We have found formation
of four polyhydrates, two of which are metastable over the whole temperature range studied. All polyhydrate crystals were
isolated and their compositions and densities determined; for (i-C5H11)4NC2H5COO·36.5H2O, unit cell parameters were additionally found. The results are compared with data for tetra-n-butylammonium carboxylate
polyhydrates, and the structure of the title compounds is suggested. It is confirmed that the isoamyl radical stabilizes the
tetradecahedral void of the clathrate hydrate framework better than the n-butyl radical.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 3, pp. 67–71, May–June, 1994.
Translated by L. Smolina 相似文献
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Weak interactions of nonaromatic amino acids with - and -cyclodextrins in aqueous solutions at 298.15 K were studied calorimetrically. The structure and solvation of these compounds noticeably affect the thermodynamic characteristics of interparticle interactions. 相似文献
6.
The reaction of phenylacetylene with CO and n-butanol in toluene (363 K) catalyzed by the Pd(dba)2/m(CF3COOH)/n(Ph3P) system (dba is dibenzylideneacetone; 2 m 8; 10 n 30) is studied. The initial rate of the main product (butyl 2-phenylpropenoate) buildup is found to depend on the pressure of CO and the concentrations of reactants and system components. The state of the catalyst under reaction conditions is studied in situby IR spectroscopy. A kinetic model is developed based on the experimental results. This model corresponds to the mechanism that resembles the hydride mechanism in the type of main intermediates in the catalytic cycle. 相似文献
7.
I. V. Terekhova O. V. Kulikov V. P. Barannikov 《Russian Journal of General Chemistry》2004,74(8):1213-1217
The possibility of isolation of crystalline supramolecular complexes of 18-crown-6 with glycine, L-alanine, L-valine, L-leucine, L-phenylalanine, L-proline, L-hystidine, and L-threonine from aqueous solutions was studied. Comparative analysis of thermal decomposition of the complexes and their individual components and mechanical mixture was studied by means of thermogravimetry, differential thermal analysis, and differential scanning calorimetry. Crystaline complexes of 18-crown-6 with glycine, L-alanine, and L-hystidine were isolated and shown to be stable up to 140°C, which was additionally confirmed by IR spectroscopy.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 8, 2004, pp. 1313–1317.Original Russian Text Copyright © 2004 by Terekhova, Kulikov, Barannikov.This revised version was published online in April 2005 with a corrected cover date. 相似文献
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Chromatographia - The retention of compounds of various classes on macroporous sulfonated cation exchangers in the form of the fourth period elements in Mendeleev's table (i. e. in the K, Ca,... 相似文献
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B. A. Vigante M. I. Terekhova Ya. Ya. Ozols E. S. Petrov G. Ya. Dubur 《Chemistry of Heterocyclic Compounds》1989,25(9):1028-1031
The patterns governing the dependence of NH-acidity on the presence of -, - and -substituents in the 1,4-dihydropyridine ring and on their nature have been established by comparison of the pKa values of monocyclic 1,4-dihydropyridines and 4,5-dihydroindenopyridines. Additional data were obtained on the influence of the the electronic effects of sulfur-containing substitutents on the reaction center in the dihydropyridine molecules.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1228–1231, September, 1989. 相似文献
10.
Data on changes in the activity of the Pd(dba)2/2TsOH/10Ph3P (dba is dibenzylideneacetone) and PdCl2(Ph3P)2/8Ph3P catalytic systems in the reaction of phenylacetylene with CO and n-butanol under the action of a solvent (aromatic hydrocarbons, chloroalkanes, ethers, esters, ketones, and dipolar aprotic media) are presented. The differences found in the response of either of the systems to changes in the properties of the medium are discussed in terms of a scheme of the catalytic cycle of reaction. It is noted that activity does not correlate with the physicochemical characteristics (polarity, basicity, and electron-acceptor ability) of solvents. 相似文献