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排序方式: 共有311条查询结果,搜索用时 203 毫秒
1.
Tatyana N. Moshkina Emiliya V. Nosova Julia V. Permyakova Galina N. Lipunova Ekaterina F. Zhilina Grigory A. Kim Pavel A. Slepukhin Valery N. Charushin 《Molecules (Basel, Switzerland)》2022,27(21)
Design and synthesis of 2-(aryl/thiophen-2-yl)quinazolin-4(3H)-ones and 4-cyano-2-arylquinazolines with Et2N-, Ph2N- or carbazol-9-yl- electron donating fragment are described. The key photophysical properties of these compounds have been studied by UV/Vis absorption and fluorescence spectroscopy in solvents of different polarity (toluene and MeCN). 2-(Aryl/thiophen-2-yl)quinazolin-4(3H)-ones show fluorescence in blue-green region in toluene solution with quantum yields up to 89% in the case of 2-(4’-N,N-diphenylamino[1,1’-biphenyl]-4-yl)-quinazolin-4(3H)-one. Moreover, triphenylamino derivative based on quinazolin-4(3H)-one with para-phenylene linker displays the highest quantum yield of 40% in powder. The fluorescence QY of Et2N and Ph2N derivatives decrease when going from toluene to MeCN solution, whereas carbazol-9-yl counterparts demonstrate strengthening of intensity that emphasizes the strong influence of donor fragment nature on photophysical properties. 4-Cyanoquinazolines are less emissive in both solvents, as well as, in solid state. The introduction of cyano group into position 4 leads to orange/red colored powder and dual emission bands. Some molecules demonstrate the increase in emission intensity upon addition of water to MeCN solution. According to frontier molecular orbitals (HOMO, LUMO) calculations, the energy gap of 4-cyanoquinazoline decreases by more than 1 eV compared to quinazolin-4-one, that is consistent with experimental data. 相似文献
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Yulia S. Kudyakova Yanina V. Burgart Pavel A. Slepukhin Victor I. Saloutin 《Mendeleev Communications》2012,22(5):284-286
Condensation of two moles of ethyl 2-[(2-aminophenylamino)methylidene]-3-oxo-3-(polyfluoroalkyl)propionates with 2,5-thiophene-dicarboxaldehyde results in new heteroatomic podands. X-ray data showed that in the solid state these molecules arrange in two independent chelating fragments of b-amino enone type, thiophene fragment being a spacer. 相似文献
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T. I. Filyakova A. Ya. Zapevalov M. I. Kodess P. A. Slepukhin V. I. Saloutin 《Russian Journal of Organic Chemistry》2014,50(6):854-857
Perfluoro(1,2-epoxycyclohexane) readily reacts with bifunctional nucleophiles (urea, thiourea, and benzene-1,2-diamine) via opening of the oxirane ring and subsequent heterocyclization to give fluorinated benzimidazole, 1,3-benzothiazole, and phenazine derivatives, respectively. 相似文献
7.
P. S. Silaichev P. A. Slepukhin A. N. Maslivets 《Russian Journal of Organic Chemistry》2013,49(8):1203-1207
1-Aryl-4,5-diaroyl-1H-pyrrole-2,3-diones react with 3-amino-4,6-dimethyl-2H-pyrazolo[3,4-b]-pyridine affording N-aryl-2,3-diaroyl-8,10-dimethylpyrido [2′,3′:3,4]pyrazolo[1,5-a]pyrimidine-4-carboxamides. 相似文献
8.
P. A. Slepukhin E. S. Salmina V. A. Potemkin M. A. Grishina 《Journal of Structural Chemistry》2013,54(6):1091-1100
X-ray crystallography is used to investigate heteromolecular crystals of 3,6-bis(3,5-dimethylpyrazole-1-yl)-1,2,4,5-tetrazine with NH-donating azole derivatives. The effect is studied of the structure of azole on molecular packing in the crystal and the characteristics of covalent bonds in the molecule of 3,6-disubstituted tetrazine. The distribution of electron density critical points inside crystal cells is analyzed to identify and quantitatively describe the intermolecular interactions underlying the formation of lateral and stacking motifs. 相似文献
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Denis N. Bazhin Dmitry L. Chizhov Gerd-Volker Röschenthaler Yulia S. Kudyakova Yanina V. Burgart Pavel A. Slepukhin Victor I. Saloutin Valery N. Charushin 《Tetrahedron letters》2014
1,1,1-Trifluoro-4,5,5-trimethoxyhex-3-en-2-one and lithium (2Z)-1,1,1-trifluoro-5,5-dialkoxy-4-oxohex-2-en-2-olate were synthesized for the first time via direct trifluoroacetylation of 2,3-butanedione acetal derivatives. A simple and effective approach to acetal or acyl substituted CF3-pyrazoles, 5,5′-bis(trifluoromethyl)-3,3′-bipyrazole, and, to 5-trifluoromethylfuran-3-ones is presented. 相似文献
10.
Slepukhin P. A. Krinochkin A. P. Starnovskaya E. S. Shtaitz Ya. K. Savchuk M. I. Kopchuk D. S. Egorov I. N. Santra S. Zyryanov G. V. Chupakhin O. N. 《Russian Chemical Bulletin》2022,71(7):1533-1543
The structures of six 2,2′-bipyridine derivatives containing aromatic amine moieties, namely N-aryl-4-aryl-1-(pyridin-2-yl)-6,7-dihydro-5H-cyclopenta[c]pyridine-3-amines, were studied by single-crystal X-ray diffraction. The molecular structures and the effect of the substituents of these compounds on the crystal packing are discussed.
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