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991.
Xe(OTeF5)2 reacts with Sb(OTeF5)3 under the formation of [Xe2(OTeF5)3]+[Sb(OTeF5)6]-. From SO2ClF solution a yellow solvate [F5TeOXe]+·SO2ClF· [Sb(OTeF5)6]- is formed with the crystal data: a = 1028.1(1), b = 1040.9(1), c = 1780.2(3) pm, α = 98.07(1), β = 97.68(1), γ = 105.82(1)°, space group . The O-Xe···O fragment is essentially linear (176.1(2)°), and the two Xe-O distances are quite different 197.1(4) and 242.6(4) pm. 相似文献
992.
Cyclization of amides of -carbamido--(indan-1, 3-dione-2-yl) hydrocinnamic acid gives 1-aryl-2-carbamido-1, 2, 3, 4-tetrahydro-4-azafloren-3, 9-dione. Alkaline and acid hydrolysis of these compounds are investigated. 相似文献
993.
Using some special experimental techniques for anisotropic refinement of the crystal structure of [Co(NH3)5NO2]Cl2 at high pressures gave results with an accuracy comparable to that obtained in normal conditions. The anisotropy of lattice
compression under pressure is determined by specific interactions in crystals, in particular, by NH-Cl and NH-O hydrogen bonds.
The anisotropy of compression at increased pressure is qualitatively distinct from that caused by lowered temperature for
the same structure. This difference is also due to specific interactions (hydrogen bonds) in the structure.
Institute of Solid State Chemistry, Siberian Branch, Russian Academy of Sciences (Novosibirsk). Novosibirsk State University.
Marburg University. Translated fromZhurnal Strukturnoi Khimii, Vol. 39, No. 3, pp. 433–447, May–June, 1998.
This work was supported by A. Humboldt Foundation. 相似文献
994.
R. M. Islamova Yu. I. Puzin R. Kh. Yumagulova A. A. Fatykhov L. V. Parfenova U. M. Dzhemilev Yu. B. Monakov 《Polymer Science Series A》2006,48(7):712-716
The effect of zirconocene dichloride and its indene-containing derivative on the radical polymerization of methyl methacrylate initiated by benzoyl peroxide has been studied. The influence of the metallocenes on the kinetic parameters of the process and the average degree of polymerization has been established. Concentration and temperature dependences have been measured for the initial rate of reaction and the average degree of polymerization in relation to the content of the components in the systems. The microstructure of poly(methylmethacrylate) prepared in the presence of the used initiation systems has been determined. 相似文献
995.
Yu Tang 《Tetrahedron letters》2006,47(23):3823-3825
5-Endo iodocyclization of various β,γ-unsaturated amides proceeded smoothly to give the corresponding conjugated iminolactones exclusively in satisfactory yields with the use of tBuOCl and I2 as the reagents, which proved to be much advantageous over the conventional I2/NaHCO3. 相似文献
996.
V. K. Ol’khovik Yu. V. Matveenko G. V. Kalechits A. A. Pap A. A. Zenyuk 《Russian Journal of Organic Chemistry》2006,42(8):1164-1168
Synthesis of 2-hydroxy(methoxy)-4,4′-biphenyldicarboxylic acids was developed. Based on their reactions with o-aminophenols we prepared for the first time 4,4′-bis[5-alkyl(aryl)benzoxazol-2-yl]-2-hydroxy-(alkoxy)biphenyls, which might be of interest as luminescent dyes. Hydroxy compounds in a salt form possess abnormally high Stokes shift. 相似文献
997.
Yu. A. Borisov 《Russian Chemical Bulletin》1982,31(10):2117-2118
Conclusions The bond polarity, determined as the ionic component fraction of the bond energy, is related in a linear manner to the Pauling polarity value.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No, 10, pp. 2401–2402, October, 1982.The author thanks I. V. Stankevich for discussing the work. 相似文献
998.
G. D. Varlamov Yu. M. Mamatov A. S. Shashkov 《Chemistry of Heterocyclic Compounds》1978,14(11):1184-1187
The structures of ,-bis(furfurylideneimino)silvan (furfuramide or N,N'-difurfurylidene-2-furanmethanediamine) and the product of its thermal cyclization 2,4,5-tris (-furyl)-2-imidazoline (furfurine) were confirmed by comparison of the IR, UV, 1H and 13C NMR, and mass spectra. It is shown that acetylation of the latter with acetic anhydride in the case of heating of the reagents without a solvent or in pyridine takes place with opening of the imidazoline ring and leads to the formation of 1,2-bis(-furyl)-1-acetamido-2-(-furoylamido)ethane.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1461–1464, November, 1978. 相似文献
999.
E. M. Suleimenov O. V. Morozova V. A. Raldugin Yu. V. Gatilov T. V. Rybalova M. M. Shakirov R. Seidakhmetov R. M. Aksartov S. M. Adekenov 《Chemistry of Natural Compounds》2005,41(5):556-560
Four sesquiterpene lactones with the germacrane structure were isolated from the aerial part of Stizolophus balsamita. X-ray structure analyses showed that two of them were previously known balsamin derivatives. A third was a crystalline isomorphous
mixture of the known lactone stizolin and 11,13-dihydrostizolin in a 53:47 ratio. The biological activities of the balsamin
derivatives were investigated.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 454–457, September–October, 2005. 相似文献
1000.
I. V. Aristov O. V. Bobreshova O. Yu. Strel'nikova 《Russian Journal of Electrochemistry》2002,38(5):567-569
In mixed aqueous solution of glycine and L-lysine the ionization of both amino acids increases due to the proton transfer from glycine zwitterion to lysine zwitterion. This is manifested by a considerable nonlinear (pairwise interaction of amino acids) increase in the mixed solution electroconductivity at high amino acid concentrations. The solution pH varies negligibly, as the amino acids in aqueous solutions demonstrate buffering. The refraction coefficient additively depends on glycine and L-lysine concentrations. 相似文献