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41.
Starukh G. N. Smirnova N. P. Eremenko A. M. Chuiko A. A. Abdel-Shafi A. A. Worrall D. R. Wilkinson F. 《Theoretical and Experimental Chemistry》2001,37(2):103-107
We have used fluorescent spectroscopy and laser flash photolysis to investigate the photonics of pyrene molecules in a pyrene–-cyclodextrin inclusion complex in various media. We have observed a protective effect of -cyclodextrin relative to solubilized pyrene molecules during quenching of fluorescence by Ti ions (or titanium dioxide particles) in mixed colloids. In the presence of a precursor of silica (a TEOS solution), the pyrene molecules react with the colloidal silica particles formed, and the reaction is accompanied by decomposition of the pyrene–-cyclodextrin inclusion complex and efficient photoionization of pyrene. 相似文献
42.
L. T. Eremenko L. O. Atovmyan N. I. Golovina G. V. Oreshko M. A. Fadeev 《Russian Chemical Bulletin》1987,36(9):1870-1872
Conclusions The product of conversion of O-bis(2-fluoro-2,2-dinitroethyl)nitromethylbis(2-fluoro-2,2-dinitroethyl)carboxime in methanol or ether is O-bis(2-fluoro-2,2-dinitroethyl)nitromethyl-2-fluoro-2,2-dinitroethyl-2'-fluoro-2-nitroethylenecarboxinie, the structure of which has been established by x-ray diffraction analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2019–2021, September, 1987. 相似文献
43.
Sidorov A. A. Talismanova M. O. Fomina I. G. Aleksandrov G. G. Novotortsev V. M. Demonceau A. Nefedov S. E. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2001,50(11):2206-2211
The reaction of propargylamine with the hexanuclear complex CoII
6(3-OH)2(OOCCMe3)10(HOOCCMe3)4 or the polymer [Co(OH)n(OOCCMe3)2–n]x under an argon atmosphere afforded the unstable paramagnetic tetramine complex CoII(OOCCMe3)2(H2NCH2CCH)4 (1). In air, if an excess of propargylamine is present, the latter complex is transformed into the complex CoIII(OOCCMe3)2(NH2CH2CCH)2[2-N,N"-(HCCCH2N=CHCHCH=N—CH2CCH)] (2) containing a new ligand, viz., the 1,3-di(propargylimino)propane anion, which is a formal analog of the acetylacetonate anion. In contrast to propargylamine, 1,3-diaminopropane reacted with the CoII trimethylacetate clusters in air to produce the cationic complex [CoIII{1,3-(NH2)2(CH2)3}2(OOCCMe3)2]+OOCCMe3
– (3) without entering into condensation reactions. The structures of the resulting complexes were determined by X-ray diffraction analysis. 相似文献
44.
V. V. Zakharov G. P. Bugaeva N. Yu. Andreeva L. B. Romanova L. T. Eremenko 《Russian Chemical Bulletin》1998,47(11):2226-2228
The reduction of 1-bromo-9,9-ethylenedioxypentacyclo[4.3.0.02,5.03,8.04,7]nonane-4-carboxylic acid (2) with lithium aluminum hydride and aluminum hydride in THF was studied. A new effective method for preparing 1-bromo-9,9-ethylenedioxypentacyclo[4.3.0.02,5.03,8.04,7]-non-4-ylcarbinol (1) based on reduction of2 with AlH3 under mild conditions was developed. 相似文献
45.
Korolev A. M. Eremenko L. T. Meshikhina L. V. Eremenko I. L. Aleksandrov G. G. Konovalova N. P. Lodygina V. P. 《Russian Chemical Bulletin》2003,52(8):1859-1863
New procedures were developed for the synthesis of 3,3-bis(hydroxymethyl)oxetane dinitrate (1) by O-nitration of the corresponding glycol (3) or its mononitrate (6), which were prepared by the reactions of 2,2-bis(hydroxymethyl)propane-1,3-diol (pentaerythritol) (2) mono- (4) and dinitrates (5), respectively, with alkali. A new method was devised for the synthesis of compounds 4 and 5 by the reaction of tetraol 2 with concentrated HNO3 in dichloroethane. The structures of compounds 1 and 6 were established by X-ray diffraction analysis. 相似文献
46.
B. S. Fedorov M. A. Fadeev V. V. Arakcheeva L. S. Barinova L. T. Eremenko 《Russian Chemical Bulletin》1996,45(2):376-380
A general reaction of the transformation of the fluorodinitromethyl group into the fluoronitromethyl group by denitration upon treatment with Na2SO3 or KI in aqueous formaldehyde was found. A preparative method for synthesizing fluoronitroalcohols was developed on the basis of this reaction. 相似文献
47.
T. F. Kuznetsova A. I. Rat’ko S. I. Eremenko 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(10):1618-1622
Micromesoporous samples of SiO2 were synthesized by the sol-gel method using tetraethoxysilane as a starting reagent and 1–5 wt % cetylpyridinium chloride as a template under the conditions of preadsorption of colloid silica by polyethyleneglycol macromolecules. The adsorption and texture of the samples were studied by the low-temperature nitrogen adsorption-desorption technique. Preadsorption of silica sol was shown to affect the adsorption and capillary-condensation properties of silica. The surface area and the volume of mesopores increased at cetylpyridinium concentrations higher than 1 wt %. The micropore volume increased to a maximum. The capillary-condensation hysteresis loop of H4 type transformed into an H3 loop according to the IUPAC classification. 相似文献
48.
E. S. Bazhina G. G. Aleksandrov N. N. Efimov E. A. Ugolkova V. V. Minin A. A. Sidorov V. M. Novotortsev I. L. Eremenko 《Russian Chemical Bulletin》2013,62(4):962-965
The reaction of an aqueous solution of vanadyl sulfate VOSO4·3H2O, butylmalonic acid (H2Bumal = C4H10(COOH)2), and lithium carbonate at pH ~4–5 gave crystals of the complex Li4(VO)2(Bumal)4(H2O)8]·H2O (1). The structure of complex 1 was established by X-ray diffraction analysis. The molecule of complex 1 consists of two mononuclear bischelate dianionic units {VO(Bumal)2(H2O)} linked by four lithium ions to form the hexanuclear heterometallic {V2Li4} structure. The crystals and an ethanolic solution of compound 1 were studied by ESR spectroscopy. 相似文献
49.
E. N. Egorov E. A. Mikhalyova M. A. Kiskin V. V. Pavlishchuk A. A. Sidorov I. L. Eremenko 《Russian Chemical Bulletin》2013,62(10):2141-2149
New luminescent heterometallic complexes of Eu3+ and Zn2+ were synthesized: Zn2Eu(NO3)(Piv)6(L)2 (Piv is pivalate anion, L = MeCN (1), 2,3-lutidine (2), 2,2′-bpy (3)) and [Zn2(Piv)3(2,2′-bpy)2][ZnEu(NO3)3(Piv)3(2,2′-bpy)] (4). In the case of 2,2′-bpy, the order of mixing of the reagents ([Zn(Piv)2] n , Eu(NO3)3·6H2O, and 2,2′-bpy) affects the composition of the final reaction product: the reaction of [Zn(Piv)2] n and Eu(NO3)3·6H2O (in the ratio Zn : Eu = 3 : 1) in MeCN affords complex 1 and the subsequent addition of 2,2′-bpy (Zn : L = 1 : 1) affords complex 3. Complex 4 is formed in the reaction of [Zn(Piv)2] n and 2,2′-bpy (Zn : L = 1 : 1) in MeCN followed by the addition of Eu(NO3)3·6H2O (Zn : Eu = 3 : 1). The luminescence spectra of compounds 1–4 (Zn : Eu = 3 : 1) exhibit metal-centered luminescence of Eu3+. The most efficient ligand-antenna is 2,2′-bpy, which is due to the optimum position of the triplet level of this ligand. 相似文献
50.
A. N. Gusev V. F. Shul’gin G. A. Nishchimenko S. B. Meshkova A. V. Kiriyak G. G. Aleksandrov I. L. Eremenko 《Russian Journal of Coordination Chemistry》2013,39(6):432-436
Heteroligand coordination compounds Ln(Dbm)2HL · nEtOH, where Ln is Nd(III), Yb(III), and Er(III); HDbm is dibenzoylmethane; H2L is bis(5-pyridin-2-yl-1,2,4-triazol-3-yl)methane, are synthesized and studied. The complexes are studied by elemental analysis, TGA, and IR spectroscopy. The structure of complex [Nd(Dbm)2 · HL · EtOH] · EtOH is determined by X-ray diffraction analysis. The crystals are triclinic, space group $P\bar 1$ , a = 10.2004(9), b = 11.3809(10), c = 20.9173(18) Å, α = 102.133(1)°, β = 103.568(1)°, γ = 100.306(2)°; Z = 2 (8416 reflections with I > 2σ(I), R = 0.053, Rw = 0.136). The luminescence of solid samples of the studied complexes is studied in the near-IR region. 相似文献