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991.
S. V. Fokin E. T. Kostina E. V. Tret’yakov G. V. Romanenko A. S. Bogomyakov R. Z. Sagdeev V. I. Ovcharenko 《Russian Chemical Bulletin》2013,62(3):661-671
The synthesis, structure, and magnetic properties of the products of the reaction for Cu(hfac)2 (hfac is hexafluoroacetylacetonate) with spin-labeled nitronyl nitroxides 4,4,5,5-tetramethyl-2-(1-R-1H-pyrazol-5-yl)-3-imidazoline-1-oxyl 3-oxides L5/R (R = Me, Et, Pr, Bu), viz., binuclear complex [Cu(hfac)2L5/Me]2 and chain polymer complexes [Cu(hfac)2L5/R]n, are described. The polymer heterospin chains are built according to “head-to-head” (R = Me, Et, Pr, Bu) and “head-to-tail” (R = Pr, Bu) motifs. Compound [Cu(hfac)2L5/Me]2 is characterized by the ability to reveal the reversible effect of thermally induced spin transition at a temperature about 75 K (without hysteresis). In the set of heterospin CuII compounds with spin-labeled pyrazoles, this is the earlier unknown example of a molecular complex exhibiting a similar magnetic anomaly. 相似文献
992.
A. M. Suleimanova N. G. Grigor’eva S. V. Bubennov A. F. Gizetdinova M. I. Tselyutina B. I. Kutepov 《Russian Chemical Bulletin》2013,62(2):435-437
The high catalytic activity and selectivity of zeolites HBeta and HZSM-12 were found in the synthesis of (E)-4-phenyl-3-buten-2-one by the reaction of styrene with acetic anhydride. 相似文献
993.
M. A. Malenkovskaya M. K. Grachev I. I. Levina E. E. Nifant’ev 《Russian Journal of Organic Chemistry》2013,49(12):1777-1782
New amphiphilic β-cyclodextrin derivatives containing pharmacologically important aromatic and aliphatic monocarboxylic acid fragments at both primary and secondary hydroxy groups were synthesized with the use of palmitic, acetylsalicylic, and 2-(4-isobutylphenyl)propionic acid chlorides. The position of the acyl groups in the carbohydrate fragments of β-cyclodextrin was determined by 13C NMR spectroscopy. 相似文献
994.
E. V. Shchegol’kov A. E. Ivanova Ya. V. Burgart V. I. Saloutin O. N. Chupakhin 《Russian Journal of Organic Chemistry》2013,49(3):417-420
Alkylation of 2-(trifluoromethyl)-1H-benzimidazole with 4-bromobutyl acetate gave 4-[2-(trifluoromethyl)-1H-benzimidazol-1-yl]butyl acetate which was deacylated by the action of hydrogen chloride in anhydrous ethanol. 4-[2-(Trifluoromethyl)-1H-benzimidazol-1-yl]butan-1-ol thus formed showed a moderate tuberculostatic activity. Alkylation of the title compound with chloromethyloxirane afforded a mixture of 1-chloro-3-[2-(trifluoromethyl)-1H-benzimidazol-1-yl]-propan-2-ol and 1-(oxiran-2-ylmethyl)-2-trifluoromethyl-1H-benzimidazole. A new procedure was proposed for the synthesis of 2-[(2-trifluoromethyl-1Hbenzimidazol-1-yl)methoxy]ethyl acetate. 相似文献
995.
996.
A. N. Yarkevich Z. V. Safronova L. N. Petrova A. V. Gabrelyan V. L. Zamoyski V. V. Grigor’ev S. O. Bachurin N. S. Zefirov 《Russian Journal of General Chemistry》2013,83(1):41-45
Bis(dialkylamides) of phosphoryl-substituted α,ω-dicarboxylic acids were synthesized and their biological activity was studied. 相似文献
997.
V. F. Mironov Yu. I. Sal’nikov G. A. Boos D. A. Tatarinov A. P. Nikitin 《Russian Journal of General Chemistry》2013,83(6):1087-1093
Four new compounds, asymmetrical phosphine oxides containing 2-hydroxyphenylethenyl fragment in cis-orientation with respect to the phosphine oxide: dibutyl-, diphenyl-, dibenzyl-, and dinaphthyl-2-(2-hydroxy-5-chlorophenyl)-2-phenyl-ethenylphospnine oxides, have been studied in aqueous ethanol (80 vol % of EtOH) by means of potentiometry and spectrophotometry at 25±0.1°C, and their acid-base and complexing properties estimated. 相似文献
998.
N. A. Dudina E. V. Antina G. B. Guseva A. I. V’yugin 《Russian Journal of General Chemistry》2013,83(12):2306-2308
We have compared the coordination properties of decamethyl-substituted 3,3′-bis-(dipyrrolylmethenes) (H2L) with different ms-spacers separating the dipyrrolylmethene domains: methylene -CH2-, methoxyphenylmethylene -CH(p-C6H4OMe)-, and trifluoromethylmethylene -CH(CF3)-. The stable binuclear homoligand complexes [M2L2] are formed in reactions of the ligands with Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) acetates. In the cases of all H2L ligands the thermodynamic constants of the complex formation reactions increase in the following series: Cu(II) < Cd(II) < Hg(II) < Ni(II) < Co(II) < Zn(II). The change in -CH2- ms-spacer to -CH(p-C6H4OMe)- or -CH(CF3)- results in a decrease in the constant of H2L complex formation by 1–4 orders of magnitude, the cation being the same. The influence of ms-substitution on the stability and luminescence properties of [M2L2] has been discussed. 相似文献
999.
R. I. Ibragimova S. A. Kubyshkin A. A. Fateev A. S. Krivov V. A. Fedyukevich Yu. S. Shcherbakov B. M. Mil’man N. V. Vorob’ev-Desyatovskii 《Russian Journal of General Chemistry》2013,83(12):2254-2259
We have studied the processes occurring when alkaline aqueous solution of Na[Au(CN)2] is brought in contact with activated carbon surface. It has been shown that the adsorption of the gold cyanide complex occurs via several independent routes, one of them being accompanied with the partial breakdown of the inner sphere of the compound and free cyanide ions release into the solution. The latter process decreases the gold recovery by aqueous NaOH during the high-temperature (150°C) desorption. A prolonged storage of the adsorbent saturated with [Au(CN)2]? in air produces a similar result. The reasons of the observed phenomena have been discussed. 相似文献
1000.
T. E. Kokina A. V. Tkachev L. I. Myachina S. N. Bizyaev L. A. Sheludyakova L. A. Glinskaya I. V. Korol’kov E. G. Boguslavskii S. V. Larionov 《Russian Journal of General Chemistry》2013,83(2):336-347
Coordination compounds Pd2(H2L2)Cl4 (I), Cu2(H2L2)Cl4 (II), Pd2(H2L3)Cl4 (III), and Cu2(H2L3)Cl4 (IV), where H2L2 and H2L3 are chiral bis-α-aminooxime ligands consisting of (+)-3-carene or (+)-limonene fragments and 4,4′-methylenedianiline linker, were synthesized and examined by NMR, ESR, and IR spectroscopy. The structure of [Cu(i-PrOH)CL2(μ-H2L3)CuCL2·H2O] (V) was determined by X-ray analysis. 相似文献