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1.
Chemical bonding in isolated molecules and crystals of zwitterionic pentacoordinate silicon chelates
The electronic structures of a number of zwitterionic pentacoordinate silicon chelates were investigated using the results of X-ray diffraction studies and quantum-chemical calculatoins by the MPW1PW91/6-311G(d) method. The topological analysis of the electron density distribution function and the study in the framework of the natural bond orbital partitioning scheme showed that the character of chemical bonding in the axial fragments of the molecules under consideration changes from dative to three-center, four-electron as the silicon atom assumes a trigonal-bipyramidal coordination. 相似文献
2.
3.
A. A. Korlyukov K. A. Lyssenko M. Yu. Antipin A. G. Shipov O. A. Zamyshlyaeva E. P. Kramarova Vad. V. Negrebetsky S. A. Pogozhikh Yu. E. Ovchinnikov Yu. I. Baukov 《Russian Chemical Bulletin》2004,53(9):1924-1931
The reaction of 4-(2-hydroxybenzoyl)-2,2,6,6-tetramethyl-2,6-disilamorpholine with BF3Et2O afforded (O-B)-chelate 4-[2-(difluoroboroxy)benzoyl]-2,2,6,6-tetramethyl-2,6-disilamorpholine. Treatment of the latter with BF3Et2O or SOCl2 gave rise to products of the disilamorpholine ring opening, viz., (O-B) chelate 2-(difluoroboroxy)-N,N-bis(dimethylfluorosilylmethyl)benzamide or 2-(difluoroboroxy)-N, N-bis(dimethylchlorosilylmethyl)benzamide, respectively. The structures of the compounds synthesized were confirmed by X-ray diffraction analysis and 1H, 13C, and 29Si NMR spectroscopy. High-precision X-ray diffraction study and quantum-chemical calculations demonstrated that the coordination OSi bond is absent in the two last-mentioned compounds.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1846–1853, September, 2004. 相似文献
4.
E. V. Chubarova D. G. Samsonenko H. G. Platas F. M. Dolgushin A. V. Gerasimenko M. N. Sokolov Z. A. Starikova M. Yu. Antipin V. P. Fedin 《Journal of Structural Chemistry》2004,45(6):1004-1013
Compounds of trigonal cluster chloroaqua complexes with cucurbit[8]uril were synthesized by slowly evaporating HCl solutions of chalcogenides heterometallic cubane cluster complexes of molybdenum and tungsten with cucurbit[8]uril in air; the complexes were characterized by X-ray diffraction analysis: (H3O)8[Mo3S4(H2O)2.5Cl6.5]2Cl(PdCl4)·(C48H48N32O16)· 29H2O (a = 13.3183(17) Å, b = 13.7104(18) Å, c = 18.225(3) Å; α = 80.263(3)°, β = 77. 958(3)°, γ = 87.149(4)°, V = 3207.4(7) Å3, space group P
, Z = 1, ρ(calc) = 1.900 g/cm3), (H3O)4 [Mo3S4(H2O)3Cl6]2·(C48H48N32O16)3·68H2O (a = 21.413(6) Å, c = 49.832(10) Å; γ = 120°, V = 19788(8) Å3, space group R
, Z = 3, ρ(calc) = 1.695 g/cm3), (H3O)6 [Mo3S4(H2O)3Cl6]2Cl2·(C48H48N32O16)·12H2O (a = 15.881(2) Å, b = 17.191(2) Å, c = 23.276(4) Å; β = 98.865(15)°, V = 6278.7(15) Å3, space group P21/c, Z = 2, ρ(calc) = 1.638 g/cm3), [W3S4(H2O)5Cl4]2·(C48H48N32O16)3·35H2O (a = 21.038(3) Å; α = 61.20(1)°, V = 6762.0(14) Å3, space group R
, Z = 1, ρ(calc) = 1.582 g/cm3). The [Mo3S4(H2O)3Cl6]2− anion complex was isolated as three geometrical isomers.Original Russian Text Copyright © 2004 by E. V. Chubarova, D. G. Samsonenko, H. G. Platas, F. M. Dolgushin, A. V. Gerasimenko, M. N. Sokolov, Z. A. Starikova, M. Yu. Antipin, and V. P. Fedin__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1049–1058, November–December, 2004. 相似文献
5.
V. R. Khabibulin A. V. Kulik I. V. Oshanina L. G. Bruk O. N. Temkin V. M. Nosova Yu. A. Ustynyuk V. K. Bel’skii A. I. Stash K. A. Lysenko M. Yu. Antipin 《Kinetics and Catalysis》2007,48(2):228-244
The formation mechanism of the active catalyst in the oxidative carbonylation of terminal alkynes at the ≡C-H bond has been investigated for the catalytic system Pd(OAc)2-PPh3-p-benzoquinone (Q)-MeOH. It has been demonstrated by NMR spectroscopy, X-ray crystallography, and kinetic measurements that the catalytically active palladium is in the oxidation state 0 and is bound into complexes stabilized by p-benzoquinone (PdL2Q, where L = PPh3). A mechanism is suggested for the catalytic process, which includes the formation of the complex PdL2Q, the oxidative addition of the alkyne to this complex at the ≡C-H bond, the insertion of CO into the Pd-C bond, and steps in which hydride hydrogen is intramolecularly transferred to the p-quinone. 相似文献
6.
N. I. Kirillova M. Yu. Antipin S. P. Knyazev V. A. Brattsev Yu. T. Struchkov V. I. Stanko 《Russian Chemical Bulletin》1979,28(11):2289-2295
Conclusions By a complete x-ray diffraction study of cesium 9,10,11-trimethyl-7,8-dicarba-nido-undecaborate(1-) we proved the axial orientation of the Me group attached to the B10 atom of the open face of the nido-carborane polyhedron. This serves as an additional proof of the stereospecificity of the alkylation reaction of the dicarbollide ions and the necessity for a migration stage of the boron atom with the substituent to the site of the deficient apex of the icosahedron to form a derivative with an equatorial disposition of the alkyl group.The atoms in the carborane polyhedron are numbered as in [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2474–2481, November, 1979. 相似文献
7.
M. N. Sultankhodzhaev B. Tashkhodzhaev B. B. Averkiev M. Yu. Antipin 《Chemistry of Natural Compounds》2002,38(1):78-82
The known diterpenoid alkaloids karacoline, karakanine, songorine, napelline, 12-acetylnapelline, cammaconine, and a new 7,17-secoalkaloid of the lycoctonine type, secokaraconitine, were isolated from tubers of Aconitum karacolicum. An x-ray structure analysis of the new alkaloid was performed. 相似文献
8.
A. S. Golubev N. D. Chkanikov M. Yu. Antipin Yu. T. Struchkov A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1992,41(8):1425-1429
Condensation of methyl trifluoropyruvate with 2-(3,4-dimethoxyphenyl)ethylamine, tryptamine, and (D, L)-tryptophan yielded 1-methoxycarbonyl-1-trifluoromethyl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline, 1-methoxycarbonyl-1-trifluoromethyl-1,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole, and Z-1-methoxycarbonyl-1-trifluoromethyl-3-carboxy-1,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole, respectively. The Z configuration of the latter was determined by x-ray structural analysis.A. N. Nesmayanov Institute of Organoelemental Compounds, Russian Academy of Sciences, 117813 Moscow, Russia. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1831–1836, August, 1992. 相似文献
9.
N.E. Kolobova A.B. Antonova O.M. Khitrova M.Yu. Antipin Yu.T. Struchkov 《Journal of organometallic chemistry》1977,137(1):69-78
The novel complexes CpRe(CCHPh)(CO)2 and Cp2Re2(μ-CCHPh)(CO)4 containing a terminal and a bridging phenylvinylidene ligand respectively and the binuclear complex Cp(CO)2Re[CC(Ph)C(Ph)CH2]Re(CO)2Cp were obtained in the reaction of CpRe(CO)3 with PhCCH.According to an X-ray study of the latter complex the unusual bridging ligand is η1-bonded to one Re atom and η2-bonded to the other. 相似文献
10.
A. V. Antipin N. M. Shishlov S. A. Grabovskii N. N. Kabal"nova 《Russian Chemical Bulletin》2004,53(4):800-802
The kinetics of the reaction of dimethyldioxirane with fullerene C60 was studied, and the activation parameters logk = (8.3±0.8) – (14.2±0.9)/, ( = 2.3RT kcal mol–1) (20—45°C) were determined. The formation of paramagnetic particles was detected. 相似文献