- Modified copolymers of bifunctional vinyl ethers with methyl vinyl sulfide as active matrices of solid superbases
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Reactive linear and crosslinked copolymers of diethylene glycol divinyl ether and ethylene glycol vinyl glycidyl ether with methyl vinyl sulfide have been synthesized in the presence of 2,2′-azobis(isobutyronitrile) (2%, 60 °C, 45-55 h) in ~53% yield. The hydrolyzed at the residual vinyloxy and epoxy groups and oxidized at the methylthio groups copolymers upon treatment with KOH afford alkoxide (complex) and crown-like superbases. They are capable of catalyzing the acetone ethynylation, as well as the prototropic isomerization of methyl propargyl ether to allenyl methyl ether and vinylation of ethylene and diethylene glycols with acetylene.
- Trofimov,Morozova,Mikhaleva,Markova,Tatarinova,Henkelmann
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experimental part
p. 2111 - 2116
(2010/05/02)
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- Nucleophilic addition to acetylenes in superbasic catalytic systems: XIV. Vinilation of diols in a system CsF-NaOH
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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. 2005 Pleiades Publishing, Inc.
- Oparina,Khil'ko,Chernyshova,Shaikhudinova,Parshina,Preiss,Henkelmann,Trofimov
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p. 661 - 666
(2007/10/03)
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- PYROLYTIC TRANSFORMATION OF THE VINYL MONOETHERS OF DIOLS IN THE PRESENCE OF ALKALIS
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The alkaline pyrolysis of the vinyl monoethers of diols takes place at 170-250 deg C and is accompanied by cycloacetalization (ethylene glycol, 1,3-propanediol), by processes involving cleavage of the C-O bonds (diethylene glycol, 1,4-butanediol), and also by the release of hydrogen, carbon dioxide, methane, ethane, acetylene, and C3 to C5 hydrocarbons.Distillation of ethylene glycol vinyl monoether with potassium hydroxide, sodium hydroxide, and lithium hydroxide can result in explosion as a result of the vigorous and exothermic release of gas.
- Trofimov, B. A.,Oparina, L. A.,Parshina, L. N.,Lavrov, V. I.,Grigorenko, V. I.,Zhumabekov, M. K.
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p. 1424 - 1428
(2007/10/02)
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- Vacuum-ultraviolet photlysis (185) nm of liquid 1,3-dioxan
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1,3-Dioxan photolytic destruction at 185 nm occurs with a quantum yield of about 0.3 in the liquid phase.Of the 22 products determined, the major ones are n-propylformate (φ = 0.10), formaldehyde (0.075), 1,3-diox-4-en (0.06), hydrogen (0.05), ethylene (0.04), and 3-methoxypropionaldehyde (0.04).A number of the minor products are of the general type B, some of which bear a hydroxyl function at the end of the side chain.N2O interacts with excited 1,3-dioxan, leading to the production of N2.Some experiments have been carried out in the vapour phase, the results of which indicate that considerable fragmentation of hot primary intermediates and products into low-molecular-weight products occurs.The nature of these products cannot be linked directly to the primary photolytic process inferred from the liquid-phase studies.Certain contrasts in the photolytic behaviour of 1,3-dioxan and 1,4-dioxan are discussed.
- Schuchmann, Heinz-Peter,Clemens, Sonntag von
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p. 1833 - 1839
(2007/10/02)
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- HOMOLYTIC DISPLACEMENT AT CARBON. XI. INTRAMOLECULAR HOMOLYTIC DISPLACEMENT AS A ROUTE TO CYCLOPENTANE AND TETRAHYDROFURAN DERIVATIVES FROM HEX-5-ENYL- AND HEX-3-OXO-5-ENYLCOBALOXIMES
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5-Methylhex-5-enylcobaloxime reacts with carbon tetrachloride and with fluorotrichloromethane at 80-100 deg C to give substantially pure 1-methyl-1-(Β,Β,Β-trichloroethyl)- and 1-methyl-1-(β-fluoro-β,β-dichloroethyl)-cyclopentane.Hex-5-enylcobaloxime also gives trichloroethylcyclopentane from carbon tetrachloride, but the yield is dependent on the concentration of carbon tetrachloride.Similar cyclisation to give trichloroethyl- or fluorodichloroethyltetrahydrofuran is observed in the reactions of hex-3-oxo-5-enylcobaloxime with carbon tetrachloride and fluorotrichloromethane.However, no cyclisation was observed in the reactions of the ester, hex-2-one-3-oxo-5-enylcobaloxime, with carbon tetrachloride.These reactions are believed to take place by attack of a polyhalogenomethyl radical at the terminal unsaturated carbon of the organic ligand, followed either by an intramolecular homolytic displacement in which the carbon radical at position-5 attacks carbon-1 with displacement of cobaloxime(II), or by a halogen atom abstraction.
- Bongars, Christophe,Bougeard, Peter,Bury, Adrian,Cooksey, Christopher J.,Johnson, Michael D.,et al.
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p. 163 - 172
(2007/10/02)
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- BEHAVIOR OF NONIONIC SURFACTANTS ON HEATING.
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For elucidation of the influence of individual components on the thermal properties of commercial NIS (Nonionic Surfactants) used data obtained in studies of individual model compounds corresponding to the commercial products. Investigation of individual surfactants made it possible to establish the principal routes in the mechanism of destructive conversions. It is found that the thermal stability of NIS containing oxyethylene groups is limited by the resistance of C-O bonds in oxyethylene groups to heat treatment. The main route of destructive conversions of NIS is cleavage of C-O bonds in oxyethylene groups, accompanied by migration of hydrogen atoms from beta carbon atoms to the cleavage points. Oxidation processes are accompanied by homolytic cleavage of C-O bonds in oxyethylene groups.
- Aksenova,Logovatovskaya,Khar'kov,Lebedeva,Belyaev
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p. 1881 - 1885
(2007/10/02)
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