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91.
Functionalization of the diaminodibenzocrown ethers with 2H-[1]benzopyrane and 3H-naphtho[2,1-b]pyrane units by Buchwald-Hartwig C-N coupling was developed. It is demonstrated that the novel molecule possesses photochromic properties that can be modified by the complex formation process. 相似文献
92.
Yuliya A. Volkova Ekaterina M. Budynina Tamara S. Kuznetsova Nikolai S. Zefirov 《Tetrahedron》2008,64(16):3548-3553
A novel approach to acyclic alkyldinitronitronates using nucleophilic opening of epoxides with the trinitromethyl anion is presented. The scope and limitations of this synthetic procedure are presented. A series of highly functionalized 3,3-dinitroisoxazolidines were synthesized as mixtures of diastereomers. 相似文献
93.
Ekaterina V. Matveeva 《Tetrahedron letters》2008,49(42):6129-6133
Water as a solvent significantly accelerates the addition of various amines to diethyl vinylphosphonate to yield β-aminophosphonates without any catalyst compared to known procedures for such aza-Michael reactions. The products are obtained in quantitative yields and high purity over short reaction times. Using a reactant ratio (vinylphosphonate/amine) of 2:1 resulted in double phosphorylation of primary amines. 相似文献
94.
The iodination of 6-aryl-2-pyrones with iodine chloride in glacial acetic acid leads to the corresponding 3-iodo derivatives. 3-Cyano-6-phenyl-2-pyrone and 3-phenylethynyl-6-phenyl-2-pyrone were obtained by replacement of the iodo group by cyano and phenylethynyl groups.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 616–618, May, 1884. 相似文献
95.
96.
Bogdan Kurtev Ekaterina Simova Maya Victorova Nikolina Berova Stefanka Christoskova 《Monatshefte für Chemie / Chemical Monthly》1981,112(5):669-673
Diphenylhalonium salts were used in stereospecific N-phenylation of racemic and optically active 3-amino-2,3-diphenyl-1-propanols leading to 3-anilino-2,3-diphenyl-1-propanols. The absolute configurations of the latter and of genetically related compounds were established.
Stereochemische Korrelation von diastereomeren 3-Amino- mit 3-Arylaminosäuren bzw. ihrer Derivate durch stereospezifische N-Phenylierung mit DiphenylhaloniumsalzenKurze Mitteilung
Zusammenfassung Durch stereospezifische N-Phenylierung mit Hilfe von Diphenylhaloniumsalzen werden racemische sowie optische aktive 3-Amino-2,3-diphenyl-1-propanole in die entsprechenden 3-Anilino-2,3-diphenyl-1-propanole übergeführt. Auf Grund dieser Umwandlung wird die absolute Konfiguration der Aminoalkohole und davon abgeleiteter Derivate ermittelt.相似文献
97.
98.
光学特异材料的设计 总被引:2,自引:0,他引:2
Christian Helgert Thomas Pertsch Carsten Rockstuhl Ekaterina PshenaySeverin Christoph Menzel ErnstBernhard Kleyet.al 《中国光学》2010,3(1):1-10
In this contribution we review our latest achievements of combined experimental and theoretical studies to tailor the properties of optical metamaterials(MMs) at will. We give three examples of metamaterial designs that have been realized by means of electron-beam lithography and whose spectroscopic characteristics have been comprehensively investigated. In every case, our experiments are complemented by rigorous numer ical simulations. Particular emphasis is put on the significance of such tailored effective properties of optical MMs 相似文献
99.
Ekaterina A. Ilyina Carla Cirillo Carmine Attanasio 《Physica C: Superconductivity and its Applications》2010,470(19):877-879
Current–voltage (I–V) characteristics and critical current density, Jc, for the onset of vortex motion were measured at different magnetic fields, H, and temperatures, T, in a superconducting (S)/ferromagnetic (F) bilayer and in a single Nb film. We choose Nb as a superconductor and a weak ferromagnetic alloy, Pd1−xNix with x = 16, as F. We found that Jc was smaller for the S/F bilayer with respect to the single Nb film. The result was related to the reduced value of the superconducting order parameter in the bilayer. 相似文献
100.
Ekaterina Vl. Bulinskaya 《Stochastic Processes and their Applications》2018,128(7):2325-2340
For a supercritical catalytic branching random walk on , , with an arbitrary finite catalysts set we study the spread of particles population as time grows to infinity. It is shown that in the result of the proper normalization of the particles positions in the limit there are a.s. no particles outside the closed convex surface in which we call the propagation front and, under condition of infinite number of visits of the catalysts set, a.s. there exist particles on the propagation front. We also demonstrate that the propagation front is asymptotically densely populated and derive its alternative representation. 相似文献