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31.
O. N. Chechina S. V. Sokolov A. P. Tomilov 《Russian Journal of General Chemistry》2004,74(11):1714-1718
Carboxylic acids prepared from hexafluoropropene oxide CF3CF2CF2O[CF(CF3)CF2O]nCF (CF3)COOH [n = 0, 2,5-bis(trifluoromethyl)-3,6-dioxaperfluorononanoic acid; n = 1, 2,5,8- tris(trifluoromethyl)-3,6,9-trioxaperfluorododecanoic acid], according to voltammetric data, enter the Kolbe reaction both at the Pt anode and at anodes from carbon materials in H2O-CH3CN and CH3OH-CH3CN solutions. The critical potential appreciably depends both on the anode material and on the solvent composition. Favorable effect of pyridine additions in H2O-CH3CN solutions is due to replacement of water molecules from the electrical double layer. The sodium ions exert a negative effect on the Kolbe synthesis.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1842–1846.Original Russian Text Copyright © 2004 by Chechina, Sokolov, Tomilov.This revised version was published online in April 2005 with a corrected cover date. 相似文献
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A. V. Virovets N. V. Podberezskaya M. N. Sokolov I. V. Korobkov V. P. Fedin V. E. Fedorov 《Journal of Structural Chemistry》1993,34(2):292-295
The crystal structure was determined for Nb2S4(S2NCEt2)4 obtained in 48% yield by the reaction of Cs4Nb2S4(NCS)8 with NaS2CNEt2 in water: a=21.181(8), b=6.958(1), c=16.623(6) Å, =133.95(2)o, V = 1764(1) Å3, space group C2/m, Z=2, dcalc=1.708 g/cm3. The measurements were carried out on a Syntex P21 diffractometer with CuK radiation. A total of 2536 reflections were measured, of which 990 were used, Raniso=0.0444. The basic fragment in this molecule is [Nb2(2–S2)2]4+, the Nb–Nb distance in which corresponds to a metal-metal single bond. The molecule is partially disordered over two positions about the twofold axis and mirror plane of the C2/m space group. The dithiocarbamate and disulfide ligands with bidentate coordination form a distorted square antiprism about each of the niobium atoms as in NbS2Cl2. The anomalously large S–S bond length in the S2 ligand [2.282(5) Å] may be attributed to inaccuracy in the determination due to disorder.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 2, pp. 134–138, March–April, 1993. 相似文献
36.
V. I. Sokolov 《Russian Journal of Coordination Chemistry》2007,33(10):711-724
Fullerenes are considered as ligands in transition metal π-complexes. The following aspects are discussed: metals able to form complexes with fullerenes; haptic numbers; homo-and heteroligand complexes; ligand compatibility with fullerenes for different metals, including fullerenes with a disturbed structure of conjugation. 相似文献
37.
V. I. Sokolov 《Russian Chemical Bulletin》1993,42(1):1-11
The preparation, structure, and reactivity of the family of polyhedral carbon clusters, novel allotropes of carbon, are reviewed.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 10–19, January, 1993. 相似文献
38.
The behavior of hexafluoroacetone ethoxycarbonylimine in cyclocondensation with different binucleophiles of the amidine type, viz., amino derivatives of N- and N,S-heterocycles, was studied. A preparative method for the synthesis of previously unknown annelated 2,2-bis(trifluoromethyl)-1,3,5-triazinones was developed. 相似文献
39.
D. N. Dybtsev I. E. Sokolov E. V. Peresypkina V. P. Fedin 《Russian Chemical Bulletin》2007,56(2):225-230
Two new scaffold-like metal-organic coordination polymers, [Zn2ndc2bpe]·DMF and [Zn2ndc2dedpbp] ·4DMF (ndc is 2,6-naphthalenedicarboxylate, bpe is trans-bis(4-pyridyl)ethylene, and dedpbp is 4,4′-diethynyl-4″,4′″-dipyridylbiphenyl), were synthesized by heating stoichiometric
amounts of zinc(II) nitrate, H2ndc, and bpe or dedpbp in DMF. The structures of the polymers were established by X-ray diffraction. Coordination of linear
dicarboxylate ligands to zinc cations gives rise to planar square-grid networks, and additional coordination of the bifunctional
nitrogen-containing ligands results in the formation of scaffold-like triply interpenetrating structures with a primitive
cubic topology.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 219–223, February, 2007. 相似文献
40.
V. P. Sokolov N. M. Zaidman V. I. Shport Y. A. Alabuzhev 《Reaction Kinetics and Catalysis Letters》1977,6(3):329-333
Under reforming conditions, the rate of n-heptane conversion on a large Pt/Al2O3 catalyst grain, in contrast to that in the kinetic region, depends on the hydrogen to hydrocarbon mole ratio. The rate equation for the reaction on a large grain agrees well with the experimental results obtained by a gradientless method under pressure.
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