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71.
T. V. Timofeeva E. S. Shubina A. N. Krylov L. M. Epshtein 《Russian Chemical Bulletin》1995,44(10):1845-1847
Molecular mechanics calculations of geometric parameters and energies of molecular complexes with a O-H...M hydrogen bond have been performed for osmocene and decamethylosmocene with three proton donors. The results of calculations demonstrated that when rings are methylated, steric hindrances to formation of this hydrogen bond increase. This is the reason for anomalously low formation constants of H-bonded Cp
2
*
M molecular associates compared to CP2M associates.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1925–1927, October, 1995.The work was supported by the Russian Foundation for Basic Research (Project No. 93-03-4610) and the International Science Foundation (Grant MP5 000). 相似文献
72.
L. K. Shubina S. N. Fedorov A. I. Kalinovskiy A. S. Dmitrenok J. O. Jin M. G. Song J. Y. Kwak V. A. Stonika 《Russian Chemical Bulletin》2007,56(10):2109-2114
Four new chamigrane sesquiterpenoids, (6S,10S)-10-bromo-3,11,11-trimethyl-7-methylidenespiro[5.5]undec-2-ene-4-one, (4S,6S,10S)-10-bromo-3,11,11-trimethyl-7-methylidenespiro[5.5]undec-2-ene-4-ol, (3R,4S,6S,10R)-10-bromo-3,11,11-trimethyl-7-methylidenespiro[5.5]undecane-3,4-diol, and (6S,7S,11R)-2-chloro-3,7,11-trimethyl-10-methylidenespiro[5.5]undec-2-ene-7-ol, were isolated from the sea hare Aplysia dactylomela. The chemical structures of new compounds were established by NMR spectroscopy and mass spectrometry. The cytotoxic activity
of some of the obtained compounds against promyelocytic HL-60 and monocytic THP-1 leukemia cells was demonstrated. 相似文献
73.
L. M. Epstein L. N. Saitkulova E. S. Shubina L. S. Golovchenko D. N. Kravtsov 《Russian Chemical Bulletin》1996,45(7):1749-1752
Interaction of R
n
M-derivatives of 4-nitrophenol and thiophenol (R
n
M= PhHG, PPh3Au, Ph3Sn, Ph4Sb) with a set of inorganic and organic anions (Cl–, Br–, I–, CN–, [PhOCO]–, [4-NO2C6H4OCO]–) was studied by IR and electronic spectroscopy in solvents with different polarities and coordinating properties (C6H6, CH2Cl2, DMSO). The dependence of the character of the interaction with the anions on the nature of the metal atom and heteroatom, the type of anions and the nature of the media was analyzed. Such interaction leads to ion-molecular complexes, and also to dissociation of the X-M bond (X = O, S, M = Au, Hg. Sb) with formation of the (4-NO2C6H4X)– anion even in weakly polar media. Only in the case of 4-NO2C6H4OSnPh3 does the reaction stop at the stage of complex formation. In other cases the role of complex formation with anions is less than with neutral coordinating reagents.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1838–1841, July, 1996. 相似文献
74.
V. N. Tsupreva O. A. Filippov F. M. Dolgushin K. I. Tugashov A. I. Krylova V. I. Bragin I. A. Tikhonova V. B. Shur L. M. Epstein E. S. Shubina 《Russian Chemical Bulletin》2008,57(12):2540-2547
As was shown by IR spectroscopy, the reaction of the three-mercury anticrown (o-C6F4Hg)3 (1) with the [H3BCN]ion in THF affords the complexes {[(o-C6F4Hg)3][H3BCN](5) and [(o-C6F4Hg)3]2[H3BCN](6). Complex 6 was isolated from solution in the analytically pure state. According to X-ray diffraction data, complex 6 has a double-decker sandwich structure, in which the borohydride group of the [H3BCN]? anion is bound to one anticrown molecule by three B-H-Hg bridges, whereas the cyanide group is cooperatively coordinated by three mercury centers of another molecule 1 through the nitrogen atom. The reaction of compound 1 with triethylamineborane Et3NBH3 in THF affords the 1: 1 complex ~[(o-C6F4Hg)3][Et3NBH3]~ (7). In this adduct, the binding of the aminoborane to the mercury anticrown is also accomplished by B-H-Hg bridges. The stability constants of complexes 5 and 6 in THF were determined. 相似文献
75.
Gutsul E. I. Belkova N. V. Babakhina G. M. Epstein L. M. Shubina E. S. Bianchini C. Peruzzini M. Zanobini F. 《Russian Chemical Bulletin》2003,52(5):1204-1206
According to low-temperature UV-Vis spectroscopy data, the two-step protonation of iron subgroup metal hydrides [{P(CH2CH2PPh2)3}MH2] (M = Fe, Ru, Os) with p-nitrophenol includes the formation of ion pairs stabilized by a hydrogen bond between the cationic dihydrogen complex and the phenolate anion. The trend of the extent of proton transfer appeared to be aperiodic, FeI OsI < RuI, in contrast to the previously obtained sequence of the proton-acceptor capacity of the hydride ligand, which increases down the group. 相似文献
76.
77.
Alexey N. Bilyachenko Mikhail M. Levitsky Alexey I. Yalymov Alexander A. Korlyukov Viktor N. Khrustalev Anna V. Vologzhanina Lidia S. Shul'pina Nikolay S. Ikonnikov Alexander E. Trigub Pavel V. Dorovatovskii Xavier Bantreil Frdric Lamaty Jrme Long Joulia Larionova Igor E. Golub Elena S. Shubina Georgiy B. Shul'pin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(49):15586-15589
A series of four unprecedented heterometallic metallagermsesquioxanes were synthesized. Their cage‐like architectures have a unique type of molecular topology consisting of the hexairon oxo {Fe6O19} core surrounded in a triangular manner by three cyclic germoxanolates [PhGe(O)O]5. This structural organization induces antiferromagnetic interactions between the FeIII ions through the oxygen atoms. Evaluated for this first time in catalysis, these compounds showed a high catalytic activity in the oxidation of alkanes and the oxidative formation of benzamides from alcohols. 相似文献
78.
Aleksei A. Titov Alexander F. Smol’yakov Kristina F. Baranova Oleg A. Filippov Elena S. Shubina 《Mendeleev Communications》2018,28(4):387-389
Reaction of a trinuclear silver pyrazolate {[3,5-(CF3)2Pz]Ag}3 complex with tricyclohexylphosphine at different reagent ratios leads to the formation of heteroleptic dinuclear or tetranuclear complexes. According to the single crystal X-ray analysis of the dinuclear complex, hexane molecules are incorporated into the cavities formed as the result of supramolecular packing. Coordination of a phosphine ligand makes dinuclear silver pyrazolate to exhibit blue emission at room temperature. 相似文献
79.
L. Yu. Filippova V. N. Shubina N. P. Kozlova S. B. Putin 《Russian Journal of Applied Chemistry》2013,86(9):1388-1391
Adsorption properties of synthesized metal-organic frameworks based on 1,4-dicarboxylate ligands and zinc ions were studied. It was shown that the adsorption properties of these metal-organic frameworks in relation to water and benzene are much higher than those for the known adsorbents: KT-1 and KT-2 coals, USY and ZSM-5 zeolites, and pentasil. 相似文献
80.
P. A. Karaseov O. A. Podsvirov A. I. Titov K. V. Karabeshkin A. Ya. Vinogradov V. S. Belyakov A. V. Arkhipov L. M. Nikulina A. L. Shakhmin E. N. Shubina N. N. Karasev 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(1):45-49
It is established that the addition of hydrogen to methane in the reaction mixture upon the fabrication of diamond-like carbon films via the plasma-enhanced chemical vapor deposition method decreases residual stresses in the obtained films and significantly reduces their growth rate. The films were investigated via atomic force microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. Irradiation of the prepared films with P+ and PF 4 + ions results in strong sample swelling with increasing dose, as well as in a decrease in the compressive stress up to transition to tensile one reaching saturation. Moreover, the fraction of sp 3 bonds increases with increasing ion dose while the fraction of sp 2 bonds decreases symmetrically with the processes proceeding faster upon irradiation with molecular ions. Qualitative mechanisms explaining the experimental results are proposed. 相似文献