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291.
A. V. Afonin I. A. Ushakov D. E. Simonenko E. Yu. Schmidt N. V. Zorina A. V. Ivanov A. M. Vasil’tsov A. I. Mikhaleva 《Chemistry of Heterocyclic Compounds》2008,44(10):1238-1244
It has been discovered that the chemical shifts of carbon atoms in 13C NMR spectra of oximes having pyrrolyl, furyl, benzofuryl, thienyl, and pyridyl rings as substituents are changed systematically
on going from the E- to the Z-isomer. This makes it possible to use the indicated chemical shifts for establishing the configuration of oximes with heterocyclic
substituents and studying the special features of their electronic structure.
Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1523–1531, October, 2008. 相似文献
292.
The modification of surfaces of solid-state potentiometric surfactant sensors with nanofiltration membranes (molecular sieves) with different diameters allows the detection of homologues of anionic, cationic, and nonionic surfactants. The quantitative characteristics of the membrane transport (permeability and ion flow) and the separating ability of plasticized polyvinyl chloride molecular sieves are evaluated. The permeabilities of nanofiltration membranes and ion flows through them depend on the nature of the blowing agent and the nature and concentration of the surfactants in the contacting solutions whose variation allows the separation of homologues of sodium alkyl sulfates, alkylpyridinium chlorides, and polyethoxylated nonylphenols in multicomponent mixtures. 相似文献
293.
O. V. Petrova L. N. Sobenina I. A. Ushakov A. I. Mikhaleva 《Russian Journal of Organic Chemistry》2008,44(10):1512-1516
1H-Indole and 2-methyl-1H-indole reacted with ethyl 3-bromopropynoate over aluminum oxide to give mixtures of the corresponding ethyl 3-(1H-indol-3-yl)propynoates and ethyl 3,3-bis(1H-indol-3-yl)-acrylates, the latter prevailing. 相似文献
294.
Boris A. Trofimov Elena Yu. SchmidtElena V. Skitaltseva Nadezhda V. ZorinaNadezhda I. Protsuk Igor A. UshakovAlbina I. Mikhaleva Oleg A. DyachenkoOlga N. Kazheva Grigorii G. Aleksandrov 《Tetrahedron letters》2011,52(33):4285-4287
2-Alkylcyclohexanones react with arylacetylenes (KOH/DMSO, 100 °C, 1 h) to afford unexpectedly hexahydroazulenones in 34-50% yields and ca. 100% diastereoselectivity (instead of the expected acetylenic alcohols), the minor products being isomeric arylethenyl ketones. 相似文献
295.
296.
N. N. Chipanina Z. V. Stepanova G. A. Gavrilova L. N. Sobenina A. I. Mikhaleva 《Russian Chemical Bulletin》2000,49(11):1914-1916
5-Phenyl-2-(1-phenyl-2-trichloroacetylethenyl)pyrrole was synthesized by the reaction of 2-phenylpyrrole with 1-phenyl-2-trichloroacetylacetylene
on silicon oxide. The structure of an intramolecular proton-transfer H-complex was assigned to the title compound based on
analysis of its IR spectra in solutions in the temperature range of 165–298 K.
Published inIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 1945–1947, November, 2000. 相似文献
297.
Boris A. Trofimov Lyubov' N. Sobenina Vladislav N. Drichkov Igor' A. Ushakov Al'bina I. Mikhaleva 《Tetrahedron》2009,65(22):4326-4331
2-Aryl-1-vinylpyrroles in acetone, THF and benzene react with tetracyanoethene chemo- and regiospecifically across the vinyl group to give 3-(2-arylpyrrol-1-yl)-1,1,2,2-cyclobutanetetracarbonitriles in 88-94% yield. The latter, upon recrystallization from EtOH, eliminates HCN and entirely rearranges to afford stereospecifically trans-(3E)-4-(2-arylpyrrol-1-yl)-1,3-butadiene-1,1,2-tricarbonitriles. In DMSO, along with the above [2+2]-cycloaddition, tricyanovinylation of the pyrrole ring occurs to form the corresponding 3- and 5-tricyanovinylpyrroles, the product ratio being dependent on the substituents in the pyrrole ring and the reaction conditions. 相似文献
298.
299.
B. A. Trofimov M. V. Markova L. V. Morozova A. I. Mikhaleva E. Yu. Shmidt N. V. Zorina Sang Heon Hyun 《Polymer Science Series B》2010,52(3-4):193-197
Polymers of 1,4-bis[2-(N-vinyl)pyrrolyl]benzene with free N-vinyl groups in side chains are synthesized in the presence of AIBN (2–5 wt %, 70°C) with a yield of up to 34% and a molecular mass of up to 11.5 × 103. In the presence of cationic catalysts (Me3SiCl, the LiBF4-dimethoxyethane system, and BF3 · OEt2), 1,4-bis[2-(N-vinyl)pyrrolyl]benzene gives macromolecules with alternating 1,2-pyrrolene and ethylidene units in the backbone with yields of 80, 44, and 33%, respectively. The polymers demonstrate paramagnetic and luminescent properties. 相似文献
300.
Boris A. Trofimov Prof. Elena Yu. Schmidt Dr. Igor' A. Ushakov Dr. Nadezhda V. Zorina Dr. Elena V. Skital'tseva Nadezhda I. Protsuk Dr. Al'bina I. Mikhaleva Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(28):8516-8521
Alkylaryl‐ and alkylheteroarylketones, including those with condensed aromatic moieties, are readily vinylated with arylacetylenes (KOH/DMSO, 100 °C, 1 h) to give regio‐ and stereoselectively the (E)‐β‐γ‐ethylenic ketones ((E)‐3‐buten‐1‐ones) in 61–84 % yields and with approximately 100 % stereoselectivity. This vinylation represents a new C(sp3)? C(sp2) bond‐forming reaction of high synthetic potential. 相似文献