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Gensch T Rönnefahrt M Czerwonka R Jäger A Kataeva O Bauer I Knölker HJ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(3):770-776
Pd(II) caught in the act: The diaryl Pd(II) intermediate of a Pd(II)-catalyzed oxidative biaryl bond formation proceeding via a double C-H bond activation has been isolated and fully characterized, including an X-ray crystal structure analysis. Stabilization due to chelation by adjacent pivaloyloxy and acetyl groups has allowed the isolation of this long-sought crucial intermediate. On gentle warming, the complex is transformed into a carbazole product, and the catalytically active Pd(II) species is regenerated by oxidation with Cu(II). 相似文献
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Saini R Boland S Kataeva O Schmidt AW Kurzchalia TV Knölker HJ 《Organic & biomolecular chemistry》2012,10(21):4159-4163
A stereoselective synthesis of (25S)-Δ(1)-, (25S)-Δ(1,4)-, (25S)-Δ(1,7)-, (25S)-Δ(8(14))-, (25S)-Δ(4,6,8(14))-dafachronic acid, methyl (25S)-Δ(1,4)-dafachronate and (25S)-5α-hydroxy-3,6-dioxocholest-7-en-26-oic acid is described. (25S)-Δ(1,4)-Dafachronic acid and its methyl ester are natural products isolated from corals and have been obtained by synthesis for the first time. (25S)-5α-Hydroxy-3,6-dioxocholest-7-en-26-oic acid represents a promising synthetic precursor for cytotoxic marine steroids. 相似文献
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Zagidullin A Ganushevich Y Miluykov V Krivolapov D Kataeva O Sinyashin O Hey-Hawkins E 《Organic & biomolecular chemistry》2012,10(27):5298-5306
The reaction of 1-alkyl-1,2-diphosphacyclopenta-2,4-dienes (1-alkyl-1,2-diphospholes) (1) with diphenyldiazomethane proceeds at room temperature via unstable [3+2] cycloadducts to form bicyclic phosphiranes (2). However, 1-alkyl-1,2-diphospholes (1) react with N,alpha-diphenylnitrone or N-tert-butyl-alpha-phenylnitrone depending on the temperature to give either dimers of 1-alkyl-1-oxo-1,2-diphospholes (5) or 1-alkyl-1,7-dioxo-6-azo-1,7-diphospha-bicyclo[3.2.0]hept-2-enes (7) - phosphorus analogues of β-lactams. 相似文献
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Kataeva O. N. Litvinov I. A. Krivolapov D. B. Lodochnikova O. A. Abdel-Hafez Sh. H. Movchan A. I. Chmutova G. A. 《Russian Journal of General Chemistry》2003,73(5):776-781
The structure of acylamino derivatives of 1-(2,4,6-trichlorophenyl)-4,5-dihydropyrazol-5-one was studied by X-ray diffraction. 3-Acetylamino-1-(2,4,6-trichlorophenyl)-4,5-dihydropyrazol-5-one and 3-benzoylamino-1-(2,4,6-trichlorophenyl)-4,5-dihydropyrazol-5-one exist in crystal as CH tautomers. The nature and number of acylamino groups were found to affect the nature of intermolecular hydrogen bonds in the crystals studied. 相似文献
57.
O. N. Kataeva I. A. Litvinov V. A. Naumov I. V. Anonimova B. A. Arbuzov 《Russian Chemical Bulletin》1988,37(9):1821-1823
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2033–2036, September, 1988. 相似文献
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N. M. Ushakov G. Yu. Yurkov K. V. Zapsis D. A. Baranov N. A. Kataeva I. D. Kosobudskiĭ S. P. Gubin 《Optics and Spectroscopy》2006,100(3):414-418
The spectral characteristics in the visible range of synthesized nanocomposites based on cadmium sulfide and ultradispersed polytetrafluoroethylene are investigated experimentally. Local perturbations are found in the long-wavelength regions of the reflection and absorption spectra, which are related to the optical transitions between the critical points of the valence and conduction bands of the nanocomposite. The dispersion relations for the refractive index and the absorption coefficient are obtained for undoped and managanesedoped nanocomposites. The following important parameters of the nanocomposites are obtained from the spectral measurements: the fundamental optical absorption edge (the band gap), the refractive index (ω → 0), and the absorption coefficient. It is shown that doping with managanese affects changes in these parameters. 相似文献