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131.
Krivdin LB Khutsishvili SS Shemyakina OA Mal'kina AG Trofimov BA Contreras RH 《Magnetic resonance in chemistry : MRC》2007,45(9):758-765
Configurational assignment and conformational analysis of a series of iminodihydrofurans obtained from cyanoacetylenic alcohols were performed on the basis of experimental measurements and high-level ab initio calculations of their (13)C-(13)C spin-spin coupling constants. The title compounds were shown to form and exist in solution as the individual Z isomers, adopting the orthogonal orientation of the amino, alkylamino and dialkylamino groups and the s-trans orientation of the CONH(2) group at the C(4) position of the 2,5-dihydro-2-iminofuran moiety. 相似文献
132.
L. V. Morozova I. V. Tatarinova N. P. Kuznetsova M. V. Markova O. A. Tarasova L. M. Sinegovskaya T. I. Vakul’skaya A. I. Mikhaleva B. A. Trofimov 《Russian Chemical Bulletin》2006,55(6):1010-1014
Polyfunctionalized linear copolymers of N-allenylimidazole and di(ethylene glycol) divinyl ether with polyconjugated (polyvinylene) blocks in the main chain and exomethylene
bonds and vinyloxyethoxyethyl groups in the side chain were prepared. Using the reaction of the copolymers with CuCl2, a possibility of synthesis of polymeric metal complexes for catalysis of organic reactions was shown. The IR and ESR spectra
of the complexes were studied.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 973–977, June, 2006. 相似文献
133.
Andreas Rahm Evgeni M. Kaidashev Heidemarie Schmidt Mariana Diaconu Andreas Pöppl Rolf Böttcher Christoph Meinecke Tilman Butz Michael Lorenz Marius Grundmann 《Mikrochimica acta》2006,153(1-2):21-25
A flow injection chemiluminescence method is proposed for the determination of cobalt, based on the strong catalytic effect
of Cobalt(II) (1,10-phenanthroline)3 complex on the lucigenin-periodate reaction in alkaline medium. Under the optimum experimental conditions, the chemiluminescence
signal responded linearly to the concentration of cobalt(II) in the 1.0 × 10−9–3.0 × 10−7 g mL−1 range with a detection limit of 4.4 × 10−10 g mL−1 cobalt(II). The relative standard deviation for the determination of 5.0 × 10−8 g mL−1 of cobalt was 2.3% in eleven replicated measurements. The method was successfully applied to the determination of cobalt(II)
in pharmaceutical preparations. 相似文献
134.
The molecular approach to heterogeneous nucleation 总被引:2,自引:0,他引:2
A molecular approach to heterogeneous nucleation has been developed. The expressions for the equilibrium cluster distribution, the reversible work of the cluster formation, and the nucleation rate have been derived. Two separate statements for the work of formation were formulated. If the equilibrium cluster distribution is normalized on the monomer concentration near the substrate surface, the reversible work of formation is expressed by DeltaG(het) (I) = (F(n) (het)-F(n) (hom))-(F(1) (het)-F(1) (hom)) + DeltaG(hom) where F(n) (het) and F(n) (hom) are the Helmholtz free energies of a cluster interacting with a substrate and a cluster not interacting with the substrate, respectively. If the equilibrium cluster distribution is normalized on the monomer concentration far from the substrate surface, the work of cluster formation is given by DeltaG(het) (II) = (F(n) (het)-F(n) (hom)) + DeltaG(hom). The former expression corresponds to the approach of the classical heterogeneous nucleation theory. The cluster partition function appears to be dependent on the location of a virtual plane, which separates the volume, where the interaction of the clusters with the substrate is effective from the one where interaction is negligible. Our Monte Carlo simulations have shown that the dependence is rather weak and thus the location of the plane is not very important. According to the simulations the variation of the plane position in the range from 20 to 50 Angstroms does not lead to a considerable change of the heterogeneous nucleation rate. 相似文献
135.
L. A. Oparina M. Ya. Khil’ko N. A. Chernyshova S. I. Shaikhudinova L. N. Parshina Th. Preiss J. Henkelmann B. A. Trofimov 《Russian Journal of Organic Chemistry》2005,41(5):661-666
A new catalytic system CsF-NaOH was developed for the synthesis of mono- and divinyl ethers of alkanediols exceeding in efficiency KOH. The nucleophilic addition of diols to acetylene in the presence of this system occurs both at enhance pressure (without solvent, 140–160°C) and atmospheric pressure (in DMSO medium, 100°C) of acetylene. Conditions were established of a selective preparation in a high yield of divinyl ethers from diols.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 677–683.Original Russian Text Copyright © 2005 by Oparina, Khil’ko, Chernyshova, Shaikhudinova, Parshina, Preiss, Henkelmann, Trofimov. 相似文献
136.
B. A. Trofimov N. K. Gusarova S. F. Malysheva S. I. Shaikhudinova N. A. Belogorlova T. I. Kazantseva B. G. Sukhov G. V. Plotnikova 《Russian Journal of General Chemistry》2005,75(5):684-688
The major product of the reaction of benzyl chloride with red phosphorus in the system concentrated aqueous KOH-dioxane-phase-transfer catalyst (43–95°C, Ar) is tribenzylphosphine oxide (yield up to 61%). Under similar conditions, phosphorylation of benzyl chloride with white phosphorus occurs differently, yielding dibenzylphosphine oxide as major product. Conditions are found for preparative synthesis of dibenzylphosphine from phosphine and benzyl chloride in the system KOH-DMSO.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 5, 2005, pp. 724–728.Original Russian Text Copyright © 2005 by Trofimov, Gusarova, Malysheva, Shaikhudinova, Belogorlova, Kazantseva, Sukhov, Plotnikova. 相似文献
137.
T. N. Aksamentova A. V. Knizhnik O. A. Tarasova A. I. Mikhaleva B. A. Trofimov 《Russian Chemical Bulletin》1999,48(9):1664-1669
Dipole moments of the molecules ofO-vinyl- andO-ethylacetoximes in octane and THF were measured at different temperatures. In octane, the equilibrium mixture of stableO-vinylacetoxime conformers consists of forms with different polarity. Polarity of these conformers, which are due to rotation
about the C−O and N−O bonds, is mainly determined by the relative position of the lone electron pairs of nitrogen and oxygen
atoms. The fraction of the polar conformer increases as temperature increases, as well as on going from octane to THF. Saturation
of the vinyl group in theO-vinylacetoxime molecule nearly halves the molecular dipole moment in the nonpolar medium, which radically differentiates
this compound from vinyl ethers.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1685–1690, September, 1999. 相似文献
138.
B. A. Trofimov N. K. Gusarova S. F. Malysheva V. A. Kuimov B. G. Sukhov S. I. Shaikhudinova N. P. Tarasova Yu. V. Smetannikov O. G. Sinyashin Yu. G. Budnikova T. I. Kazantseva V. I. Smirnov 《Russian Journal of General Chemistry》2005,75(9):1367-1372
The example of the phosphorylation of styrene and 2-vinylnaphthalene with elemental phosphorus in the KOH-DMSO system at room or elevated temperature was used to show that the activated red phosphorus prepared from white phosphorus under ionizing radiation has a reactivity comparable with that of white phosphorus and significantly higher than that of ordinary technical red phosphorus. 相似文献
139.
B. A. Trofimov V. V. Nosyreva A. G. Mal'kina 《Russian Journal of Organic Chemistry》2005,41(9):1254-1259
Macrocyclic polyether dibenzo-18-crown-6 possessing a specific affinity for potassium cation inhibits ethynylation of acetone with acetylene in the presence of KOH according to Favorskii. The inhibition becomes stronger in the presence of the complex dibenzo-18-crown-6 ? KOH ? MeOH as catalyst (both in excess acetone and in DMSO). The effect does not originate from deactivation of acetone, for its aldol-like condensation is accelerated in the presence of both dibenzo-18-crown-6 and its complex (the selectivity of ethynylation sharply falls down). Thus, apart from the high basicity of the medium, activation of acetylene due to complex formation with potassium cation plays an important role in the Favorskii ethynylation of ketones. 相似文献
140.