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Konstantin N. Gavrilov Alexei A. Shiryaev Ilya V. Chuchelkin Sergey V. Zheglov Eugenie A. Rastorguev Vadim A. Davankov Armin Börner 《Tetrahedron: Asymmetry》2012,23(14):1052-1057
New P,P-bidentate diastereomeric diphosphoramidite chiral ligands with mixed stereogenic elements and a C1 backbone symmetry have been prepared from (Sa)- and (Ra)-1,1′-binaphthyl-2,2′-diol (BINOL) and (S)-N-benzyl-1-(pyrrolidin-2-yl)methanamine and are fully characterized. The use of these ligands provides up to 84% ee in the Pd-catalyzed asymmetric allylic substitution of (E)-1,3-diphenylallyl acetate and up to 95% ee in the Rh-catalyzed asymmetric hydrogenation of α-dehydrocarboxylic acid esters. The results indicate that the catalytic performance is highly affected by the axial chirality of the binaphthyl moieties of the ligand and the nature of the solvent. 相似文献
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The paper presents the results of experimental studies of radiating piezoelectric elements made on the basis of self-supported piezoelectric polymer films. The dependences of the sensitivity of these elements on the geometric parameters and frequency are investigated within a frequency band of 10?C70 kHz. A radiating device containing an ensemble of more than 4000 piezoelectric elements is constructed. 相似文献
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K. N. Gavrilov E. A. Rastorguev S. V. Zheglov N. N. Groshkin V. E. Boyko A. S. Safronov P. V. Petrovskii V. A. Davankov 《Russian Chemical Bulletin》2010,59(6):1242-1247
P,P-Bidentate diamidophosphite ligands containing the (3R,4R)-3,4-dioxy-1-(1-naphthyl)pyrrolidine-2,5-dione framework and 1,3,2-diazaphospholidine rings with the stereogenic P atoms
were obtained. The use of these ligands provides up to 85% ee in Pd-catalyzed asymmetric amination of (E)-1,3-diphenylallyl acetate and up to 95% ee in its asymmetric alkylation with dimethyl malonate. 相似文献
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A. A. Rastorguev V. I. Belyi T. P. Smirnova L. V. Yakovkina 《Journal of Structural Chemistry》2008,49(1):21-30
A method was developed for investigating hafnium dioxide films; this procedure uses a hydrogen-deuterium lamp as a source of photoluminescence (PL) excitation. Photoluminescence in HfO2 films was investigated. An analysis of the PL spectra of the films showed that they coincided with the spectra described in the literature and recorded using more powerful sources (synchrotron radiation or ArF laser). A comparison of our results with the literature data confirmed that the PL spectra of the films weakly depended on the type of the substrate used for the synthesis. The PL band intensity depends on the synthetic conditions and the annealing temperature. We analyzed the PL and excitation spectra and revealed an emission band at an energy E ~ 4 eV with a narrow excitation maximum at E max ? 4.25 eV, which was assigned to the vibronic resonance transition A 2Σ+ ? X 2Πi in the OH?* excited radical. Water was detected in the PL spectra of the HfO2 films; it is trapped as an impurity after thermal decomposition of Hf(dpm)4 in the course of film growth. The detection of water in the PL spectra of these films provides new insight into the problem of the effect of this impurity on the leakage currents and the importance of control over its content in the films. 相似文献
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K. N. Gavrilov I. V. Chuchelkin S. V. Zheglov A. A. Shiryaev O. V. Potapova I. M. Novikov E. A. Rastorguev P. V. Petrovskii V. A. Davankov 《Russian Chemical Bulletin》2012,61(10):1925-1932
The synthesis of new P*-mono- and P*,N-bidentate diamidophosphites, containing 1,3,2-diazaphospholidine rings formed starting from (2S,3S)-N 2,3-dimethyl-N 1-phenylpentane-1,2-diamine, is described. Comparison of their efficiency in the Pd-catalyzed enantioselective allylation with (E)-1,3-diphenylallyl acetate showed that up to 97% ee was reached in the reaction involving dimethyl malonate as a C-nucleophile. The Pd-catalyzed desymmetrization of N,N′-ditosyl-meso-cyclopent-4-ene-1,3-diol biscarbamate gave up to 61% ee. 相似文献
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Lyubimov S. E. Ol’shevskaya V. A. Petrovskii P. V. Rastorguev E. A. Verbitskaya T. A. Kalinin V. N. Davankov V. A. 《Russian Chemical Bulletin》2010,59(9):1836-1839
New chiral carborane-containing amidophosphites containing the BINOL fragment (BINOL stands for 2,2′-dihydroxy-1,1′-binaphthyl)
have been synthesized. The study of efficiency of these compounds as ligands in the Rh-catalyzed asymmetric hydrogenation
of enamides in supercritical carbon dioxide (scCO2) and CH2Cl2 showed that enantioselectivity of the process is considerably higher in scCO2. 相似文献
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V. I. Belyi A. A. Rastorguev A. A. Remova G. V. Romanenko N. P. Sokolova 《Journal of Structural Chemistry》2004,45(1):130-138
The molecular and crystal structure of the terbium(III) trifluoroacetate trihydrate dimer synthesized from terbium(III) carbonate was studied by X-ray diffraction (XRD) analysis. Luminescent data unambiguously show that the compound is one of the isomers of Tb2(CF3COO)6(H2O)6 composition. Evidence has been found for the presence of another isomer in the terbium(III) dimer obtained from terbium(III) hydroxide. 相似文献