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321.
Ilya A. Cherepanov Alina S. Samarskaya Ivan A. Godovikov Konstantin A. Lyssenko Anastasia A. Pankratova Valery N. Kalinin 《Tetrahedron letters》2018,59(8):727-729
A highly efficient gram-scale method for the C(4)-functionalization of sydnone imine hydrochloride derivatives was developed. This new approach was realized through consecutive reactions including the preparation of a C(3)-substituted N6-tert-butoxycarbonyl sydnone imine derivative, deprotonation with n-BuLi and reaction of the lithiated-intermediate with an electrophilic agent, and removal of the Boc protecting group. 相似文献
322.
Shmelev M. A. Gogoleva N. V. Dolgushin F. M. Lyssenko K. A. Kiskin M. A. Varaksina E. A. Taidakov I. V. Sidorov A. A. Eremenko I. L. 《Russian Journal of Coordination Chemistry》2020,46(7):493-504
Russian Journal of Coordination Chemistry - The reactions of Cd(NO3)2 ? 4H2O and Eu(NO3)3 ? 6H2O with potassium salts of the benzoic acid derivatives and 2,2'-bipyridine (Bipy) in... 相似文献
323.
Jrme Long Ivan V. Basalov Konstantin A. Lyssenko Anton V. Cherkasov Ekaterina Mamontova Yannick Guari Joulia Larionova Alexander A. Trifonov 《化学:亚洲杂志》2020,15(17):2706-2715
We report here the synthesis, structure, magnetic and photoluminescent properties of three new bifunctional Schiff‐base complexes [Dy(L1)2(py)2][B(Ph)4]?py ( 1 ), [Dy(L1)2Cl(DME)] ? 0.5DME ( 2 ) and [Dy(L2)2Cl] ? 2.5(C7H8) ( 3 ) (HL1=Phenol, 2,4‐bis(1,1‐dimethylethyl)‐6‐[[(2‐methoxy‐5‐methylphenyl)imino]methyl]; HL2=Phenol, 2,4‐bis(1,1‐dimethylethyl)‐6‐[[(2‐methoxyphenyl)imino]methyl]). The coordination environment of the Dy3+ ion and the direction of the anisotropic axis may be controlled by the combination of the substituent groups of the Schiff bases, the nature of the counter‐ions (Cl? vs. BPh4?) and the coordinative solvent molecules. A zero‐field slow relaxation of the magnetization is evidenced for all complexes but strong differences in the relaxation dynamics are observed depending on the Dy3+ site geometry. In this sense, complex 1 exhibits an anisotropy barrier of 472 cm?1, which may be favourably compared to other related examples due to the shortening of the Dy?O bond in the axial direction. Besides, the three complexes exhibit a ligand‐based luminescence making them as bifunctional magneto‐luminescent systems. 相似文献
324.
F. Becker R. BrücknerM. Langner S.I. HintschichM. Sudzius H. FröbV.G. Lyssenko K. Leo 《Superlattices and Microstructures》2011
A homogeneous microcavity is excited in two tightly focused spatially separated spots with a few μm distance. The radius of the generated cavity modes exceeds the excited regions such that the quasimodes of both spots overlap in space. Coherent coupling of the two spots via stimulated emission is observed, exhibiting a slightly lowered lasing threshold. Furthermore, the emission from both spots is phase locked with a phase difference of either 0 or π, depending on their separation. Correspondingly, the distribution of the electromagnetic field is symmetric or anti-symmetric, and the emission occurs parallel to the cavity normal or symmetrically at non-zero angles, respectively. This behaviour is understood to be determined by the spatial distribution of gain and absorption across the active cavity medium, which we confirm by numerical calculations. 相似文献
325.
326.
Konovalova IS Nelyubina YV Lyssenko KA Paponov BV Shishkin OV 《The journal of physical chemistry. A》2011,115(30):8550-8562
In this paper intra- and intermolecular interactions in crystals of 3,4-diamino-1,2,4-triazole (DAT) and its 5-methyl derivative (DAMT) were investigated in details by experimental (high-resolution X-ray diffraction) and theoretical (ab initio quantum chemistry (MP2/aug-cc-pvdz), AIM, and NBO) methods. Influence of n-π conjugation and n→σ* hyperconjugation on the geometry of DAT and DAMT molecules was shown. All intermolecular interactions in crystals of the DAT and DAMT including weak X-H···π and mixed X-H···N/X-H···π hydrogen bonds were considered. Comparison of BCP characteristics of these interactions from experimental and theoretical charge density distribution demonstrates systematic increase of bonding in isolated dimers compared with dimers in the crystal phase. The ability of amino groups in both crystals serve as proton acceptors in hydrogen bonding was confirmed. 相似文献
327.
Vadim V. Popov Stanislav A. Amelichev Ivan S. Bushmarinov Lidia S. Konstantinova Konstantin A. Lyssenko Ludmila V. Mikhalchenko Valentin V. Novikov Vadim P. Gultyai Oleg A. Rakitin 《Tetrahedron》2013
The synthesis of [1,3]dithiolo[4,5-d]dithiazolium salts from readily available zinc chelate has been developed. Chlorination of 2-oxo and 2-(dicyanomethylene) (2-oxo-1,3-dithiole-4,5-diyl) diethanethioates with SO2Cl2 followed by condensation with Me3SiN3 produced 1,2,3-dithiazolium chlorides. The structure of 5-(dicyanomethylene)[1,3]dithiolo[4,5-d][1,3,2]dithiazol-1-ium tetrafluoroborate was confirmed by powder X-ray diffraction, and its chemical bonding pattern as well as charge transfer were studied within the QTAIM framework applied to the results of plane wave DFT periodic calculations. Reduction with triphenylantimony and electrochemical reduction of [1,3]dithiolo[4,5-d]dithiazolium salts by cyclic voltammetry, chronoamperometry, and microelectrolysis at a controlled potential on a platinum electrode in acetonitrile revealed the formation of [1,3]dithiolo[4,5-d]dithiazolyl radicals, which were characterized by EPR spectroscopy. 相似文献
328.
V. M. Berestovitskaya O. S. Vasil’eva E. S. Ostroglyadov I. N. Tyurenkov I. V. Anan’ev K. A. Lyssenko V. N. Perfilova V. V. Bagmetova 《Russian Chemical Bulletin》2013,62(11):2401-2406
Acid hydrolysis of 4-(het)aryl-3,5,5-tris(alkoxycarbonyl)-2-pyrrolidones obtained by the condensation of 1,1-bis(alkoxycarbonyl)ethenes with diethyl acetylaminomalonate leads to (2R*,3R*)-3-(het)arylglutamic acid hydrochlorides. 相似文献
329.
The intra- and intermolecular interactions that make a major contribution to the formation of the crystal structure were detected and characterized in the crystal of 1-[1-(methoxycarbonylmethylthio)methyl]-3,5-dimethylisocyanurate. Topological analysis of the experimental and theoretical electron density distribution was used to reveal for the first time the role of the lp(O)...π interaction in the formation of a crystal of an isocyanurate derivative and to estimate its energy. Interactions of this type were found to occur in 74% of the fully N-substituted isocyanurate structures. 相似文献
330.
M. Yu. Antipin E. P. Ivakhnenko Yu. V. Koshchienko P. A. Knyazev M. S. Korobov A. V. Chernyshev K. A. Lyssenko A. G. Starikov V. I. Minkin 《Russian Chemical Bulletin》2013,62(8):1744-1751
Adducts of cobalt(II) bis(salicylaldiminates) and 2,4,6,8-tetra-tert-butylphenoxazin-1-one were synthesized and their molecular and crystal structures were determined. According to the ESR and magnetochemical data, the metal atom is in the low-spin trivalent state (CoIII) due to the intramolecular electron transfer to the redox-active ligand. In the solid state, the mixedligand complexes are stable in air for several months, but in solution at elevated temperatures they dissociate to the starting components. Such a behavior detected by the temperature dependence of the effective magnetic moment is explained by the quantum chemical DFT calculations of the energy barriers of possible valence tautomeric dynamics, whose values were found to be higher than the enthalpy of dissociation. 相似文献