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71.
Kalinin M. A. Antropov S. M. Medvedko A. V. Gudovannyy A. O. Lyssenko K. A. Vatsadze S. Z. 《Russian Chemical Bulletin》2021,70(11):2247-2251
Russian Chemical Bulletin - The N-arylation of N-Boc-bispidine with arylboronic acids was accomplished under the copper-catalyzed Chan—Lam—Evans reaction conditions. The reaction... 相似文献
72.
Ivan V. Lapshin Dr. Ivan V. Basalov Prof. Dr. Konstantin A. Lyssenko Anton V. Cherkasov Prof. Dr. Alexander A. Trifonov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(2):459-463
The first example of intermolecular hydrophosphination of styrene, 2-vinylpyridine and phenylacetylene with PH3 catalyzed by bis-(amido) complexes [(Me3Si)2N]2M(NHC)2 (M=Ca, Yb, Sm) coordinated by NHC ligands is described. The reactions of styrene with PH3 proceed under mild conditions in quantitative yields to afford only anti-Markovnikov product and allow for the chemoselective synthesis of primary, secondary and tertiary phosphines. Addition of phenylacetylene to PH3 regardless the initial molar substrates ratio results in the exclusive formation of a tertiary tris-(Z-styryl)-phosphine. Crucial effect of the Lewis base coordinated to the metal ion in precatalyst on catalytic activity in styrene hydrophosphination with PH3 was demonstrated. Free NHCs were also found to be able to promote addition of PH3 to styrene, however they provide much lower reaction rates compared to the metal complexes. 相似文献
73.
74.
Elena V. Matukhina Olga I. Shchegolikhina Yulia A. Molodtsova Yulia A. Pozdniakova Konstantin A. Lyssenko Viktor G. Vasil'ev Mikhail I. Buzin Dimitris E. Katsoulis 《Liquid crystals》2004,31(3):401-420
Investigations of thermotropic phase transitions performed on organocyclosiloxanes [PhSi(O)OSiR]6, where R is Me3, Me2(CH2Cl) or Me2(CH≃CH2), have revealed that all these hexamers are mesomorphic compounds. The hexamers exhibit uncommon polymesomorphic behaviour forming two quite different mesomorphic structures. The molecular arrangement in the low temperature (LT) modification is characterized by two-dimensional (2D) long-range order with hexagonal packing. The X-ray diffraction pattern and peculiarities of molecular packing in the crystal lead us to suggest that the LT-mesophase is columnar, presumably of the Colhd type. The LT-mesophase is formed by dimeric moieties, which associate with each other in column-like substructures, the ring planes not orthogonal to the stack axis. The high temperature (HT) mesophase is a plastic crystal (3D-order), where molecules take up positions in a face-centred cubic lattice. This is a very uncommon example of thermal behaviour for plastic crystals that provides a unique opportunity to bridge the gap between plastic crystalline and liquid crystalline mesomorphic behaviour. The thermal and structural properties of the mesophases depend upon the type of side groups of the hexamers. The size of the ring also affects the phase behaviour and the mesomorphic structure. This conclusion is consistent with data obtained by us earlier for cyclotetrasiloxanes. 相似文献
75.
R. Gehlhaar M. Swoboda M. Sudzius M. Hoffmann H. Fröb V.G. Lyssenko K. Leo 《Applied physics. B, Lasers and optics》2007,86(3):413-417
We report on the dynamics of laser emission from an anisotropic organic microcavity filled with the guest-host composite of
tris-(8-hydroxy quinoline) aluminium (Alq3) and 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM). In a single microcavity, a linesplitting of
0.18 THz between two perpendicularly polarized laser modes is observed. We ascribe this effect to an optical anisotropy in
the distributed Bragg reflectors surrounding the organic layer. The temporal behavior of the electromagnetic field is studied
by an up-conversion technique and shows an optical beating of 0.18 THz. Two modeling approaches are used to gain insight in
the temporal evolution and phase behavior of the two modes. Both point towards the presence of a phase-coupling mechanism
in this system.
PACS 42.55.Sa 相似文献
76.
Siavosh Mahboobi Andreas Sellmer Thomas Burgemeister Alexei Lyssenko Dieter Schollmeyer 《Monatshefte für Chemie / Chemical Monthly》2004,47(8):333-342
The synthesis of the naturally occurring and biologically active alkaloids 1 and 2, first isolated from the red ascidian Botryllus leachi by Duran et al. [1], is described and the structure proposed for Botryllazine B (1) is confirmed. The analytical data for 2-(p-hydroxybenzoyl)-4-(p-hydroxyphenyl)imidazole (2) are discussed and compared with the literature. With special emphasis of 1H NMR data the tautomerism of aroylimidazolemethanones is described. 相似文献
77.
78.
Molotov S. I. Kulikov A. S. Strelenko Yu. A. Makhova N. N. Lyssenko K. A. 《Russian Chemical Bulletin》2003,52(8):1829-1834
3-Arylazo-4-(3-ethoxycarbonylureido)furoxans, which were synthesized by the reactions of 4-amino-3-arylazofuroxans with ethoxycarbonyl isocyanate, were subjected to cascade rearrangements under the action of potassium tert-butoxide in dimethylformamide or by heating in dimethyl sulfoxide to form 4-amino-2-aryl-5-nitro-2H-1,2,3-triazoles. X-ray diffraction study and quantum-chemical calculations (B3LYP/6-31G**) of one of ureidofuroxans demonstrated that the intramolecular contact between the carbonyl group and the nitrogen atom of furoxan corresponds to the charge transfer from the lone electron pair of the oxygen atom to the antibonding orbital of the N—O bond. 相似文献
79.
80.
T. A. Peganova N. V. Vologdin P. V. Petrovskii I. D. Nesterov K. A. Lyssenko O. V. Gusev 《Russian Chemical Bulletin》2006,55(4):683-686
The reaction of equimolar amounts of M(η5-C5H4PPh2)2 (M = Fe, Ru, or Os) and [Ru(H2O)6](OTs)2 afforded the M(η5-C5H4PPh2)2Ru(H2O)2(OTs)2 complexes, which were characterized by elemental analysis and 1H, 13C, and 31P NMR spectroscopy. The structure of the osmocene complex was established by X-ray diffraction.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 659—661, April, 2006. 相似文献