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131.
132.
Olga Fedorova Elena Lukovskaya Artem Mizerev Yury Fedorov Alla Bobylyova Anton Maksimov Anna Moiseeva Aleksander Anisimov Gediminas Jonusauskas 《Journal of Physical Organic Chemistry》2010,23(3):246-254
A novel ditopic receptor was constructed as a combination of bisthiophene with pyridinylvinyl and crown‐containing styryl fragments. In the receptor, the pyridine residue was able to coordinate Fe2+, Cd2+, and Mg2+ metal cations, whereas the oxocrown ether moiety bound with the alkaline earth metal (Mg2+, Ca2+, and Ba2+) cations. 1H NMR, optical, electrochemical, and ESI‐MS results provided conclusive evidence of a complex formation through both the coordination centers of the molecule. The obtained results showed that cation complexation induces optical and electrochemical changes, particularly for each binding center. This type of multiparameter sensor provides interesting perspectives for the future design of unique sensors, promising different analytical techniques. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
133.
Valentina V. Vasilevskaya Artem A. Aerov Alexei R. Khokhlov 《Colloid and polymer science》2006,284(5):459-467
Emulsions may be used to speed up reactions of surface-active reagents. In this paper, a theoretical analysis of a simple
catalytic reaction (A + B → P + B) is performed, where the substrate A in the presence of the catalyst B in an emulsion is converted into the product P, and both the substrate A and the catalyst B are surfactants. It was shown that, because molecules A and B are concentrated in surface layers of the emulsion, these layers act as nanoreactors ensuring a significant acceleration
of the catalytic reaction within a certain range of emulsion droplet sizes. The reaction rate depends significantly on the
emulsion droplet’s size and there exists an optimal droplet size at which the reaction acceleration is maximal. If the product
of the reaction is not surface-active, the reaction rate can remain practically unchanged up to virtually complete substrate
conversion. Besides, it was shown that the Michaelis–Menten-type dependence of the reaction rate on the substrate concentration
(i.e., the increase in the rate with subsequent saturation) can be observed in the system under consideration. 相似文献
134.
A new approach toward the synthesis of 1H-isochromenes based on the recyclization of the furan ring in the corresponding ortho-hydroxymethylbenzylfurans is described. 相似文献
135.
A. M. Kolchinskaya A. N. Artem’ev V. E. Dmitrienko F. V. Zabelin A. G. Maevskiĭ E. N. Ovchinnikova A. P. Oreshko V. A. Sarkisyan Y. Joly 《Crystallography Reports》2006,51(2):192-200
Extended X-ray absorption fine-structure spectra of yttrium-iron garnet, measured near the absorption edges of iron and yttrium at the Kurchatov synchrotron radiation source are reported. Numerical simulation of the X-ray absorption near-edge structure of these spectra is performed and good agreement with the experimental data is obtained. It is shown theoretically that “forbidden” Bragg reflections can be observed near the absorption edges of iron and yttrium. The indices of these reflections are determined. The energy structure of the “forbidden” reflections 006 and 110 is calculated. 相似文献
136.
Pavel S. Gribanov Dmitry A. Loginov Dmitry A. Lypenko Artem V. Dmitriev Sergey I. Pozin Alexey E. Aleksandrov Alexey R. Tameev Igor L. Martynov Andrey Yu. Chernyadyev Sergey N. Osipov 《Molecules (Basel, Switzerland)》2021,26(24)
Three new benzothiadiazole (BTD)-containing luminophores with different configurations of aryl linkers have been prepared via Pd-catalyzed cross-coupling Suzuki and Buchwald–Hartwig reactions. Photophysical and electroluminescent properties of the compounds were investigated to estimate their potential for optoelectronic applications. All synthesized structures have sufficiently high quantum yields in film. The BTD with aryl bridged carbazole unit demonstrated the highest electrons and holes mobility in a series. OLED with light-emitting layer (EML) based on this compound exhibited the highest brightness, as well as current and luminous efficiency. The synthesized compounds are not only luminophores with a high photoluminescence quantum yield, but also active transport centers for charge carriers in EML of OLED devices. 相似文献
137.
138.
Edward Karakhanov Yulia Kardasheva Artem Kirillov Anton Maximov Viktoriya Predeina Elena Runova 《Macromolecular Symposia》2000,156(1):137-146
A number of macromolecular and supramolecular catalysts which combine the functions of transition metal complex, phase transfer agent with molecular recognition ability has been designed. The complexes of rhodium, palladium, iron and copper showed the remarkable activity in hydroformylation, Wacker‐type oxidation of various olefins, oxidation of alkanes and hydroxylation of aromatics. 相似文献
139.
Eugene V. Tretyakov Svyatoslav E. TolstikovElena V. Gorelik Matvey V. FedinGalina V. Romanenko Artem S. BogomyakovVictor I. Ovcharenko 《Polyhedron》2008
It was established that the reactions of pyrazol-3-yl-substituted nitronyl nitroxide (HL1) and pyrazol-3-yl-substituted imino nitroxide (HL3) with Cu(II) acetate lead to self-assembly of the Cu4(OH)2(OAc)4(DMF)2(L1)2 tetranuclear and Cu2(OAc)2(H2O)2(L3)2 dinuclear complexes, respectively. The reaction of Cu(II) acetate with 5-ethoxycarbonyl-pyrazol-3-yl-substituted nitronyl nitroxide (HL2) gave unexpected solid Cu2(H2O)2(L6)2 · 2DMF, in which L6 is a deprotonated 5-carboxy-pyrazol-3-yl-substituted nitronyl nitroxide, formed as a result of cleavage of an ester bond in the starting HL2. A similar transformation of the paramagnetic ligand was observed in the reaction of Cu(II) acetate with 5-ethoxycarbonyl-pyrazol-3-yl-substituted imino nitroxide (HL4). It led to the formation of Cu2(DMF)2(L7)2, where L7 is deprotonated 2-(5-carboxy-1H-pyrazol-3-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole 3-oxide. An X-ray diffraction study indicated that in Cu4(OH)2(OAc)4(DMF)2(L1)2 and Cu2(OAc)2(H2O)2(L3)2, the L1 and L3 paramagnetic ligands perform the bridging cyclic tridentate function, while in Cu2(H2O)2(L6)2 · 2DMF and Cu2(DMF)2(L7)2, the paramagnetic L6 and diamagnetic L7 are bridging bicyclic tetradentate ligands. The magnetic behavior of complexes with coordinated nitronyl nitroxide – Cu4(OH)2(OAc)4(DMF)2(L1)2 and Cu2(H2O)2(L6)2 · 2DMF is dictated by the dominant antiferromagnetic exchange interactions, which is confirmed by quantum-chemical data. The magnetic susceptibility of Cu2(OAc)2(H2O)2(L3)2 reflects the competition between the antiferromagnetic and ferromagnetic components, of which the latter is due to electron coupling in the Cu(II) ← N=C–N ? O exchange channels. EPR data confirm the results received from static magnetic measurements for multispin solids. 相似文献