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161.
162.
163.
N. M. Vitkovskaya V. B. Kobychev E. Yu. Larionova B. A. Trofimov 《Russian Chemical Bulletin》1999,48(1):35-41
The pathways of migration of the multiple bond in propene and propyne molecules involving the hydroxide ion were investigated
by theab initio (RHF/6-31+G* and MP2/6-31+G*) methods. Stationary points corresponding to stable complexes between the molecules under study and the hydroxide ion and
between corresponding carbanions and water molecule were found on the potential energy surfaces of the proton transfer reactions.
In the presence of hydroxide ion, migration of the multiple bond can occur by an “intramolecular” mechanism of the proton
transfer involving the proton of hydroxide ion bound in the complex with propene or propyne molecule. For the propene system,
such a mechanism seems to be quite realistic and more preferable energetically than a traditional two-stage mechanism with
a passage of the proton into the medium. For the system with the triple bond, an equal expenditure of energy is required to
follow any mechanism (without taking into account the effects of solvation and the interaction with a cation), whereas the
formation of the stable [H2C=C=CH·H2O]− complex can prevent further transformations.
For Part 1, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 35–41, January, 1999. 相似文献
164.
E. I. Trofimov 《Journal of Mathematical Sciences》1990,50(5):1877-1884
We consider stochastic integrals with a parameter in the components. Inequalities for the functional norms of stochastic integrals are derived, generalizing the known inequalities of M. Emery [1] and P.-A. Meyer [2] to triples of spaces connected by the multiplication operation.Translated from Issledovaniya po Prikladnoi Matematike, Kazan', No. 14, pp. 134–143, 1987. 相似文献
165.
166.
The laws governing the propagation of diffracting beams in a two-component gaseous mixture are investigated on the basis of
a computer simulation. It is discovered that several regions with high concentrations of the reaction product form. It is
also found that the beam focus can move both in the direction of beam propagation and in the counter direction, and the change
in its position can occur abruptly. It is shown that as time goes on, a high concentration of the reaction product is achieved
in the central unilluminated region of the medium near the entrance cross section on account of diffusion (i.e., a diffusional
concentration growth occurs). This leads to the formation of a dynamic concentration maximum in this region of the medium.
Zh. Tekh. Fiz. 68, 8–14 (March 1998) 相似文献
167.
168.
S. E. Korostovka A. I. Mikhaleva B. A. Trofimov S. G. Shevchenko M. V. Sigalov 《Chemistry of Heterocyclic Compounds》1992,28(4):406-408
2-Methyl-5-phenyl- and 2,5-diphenylpyrrole and 2-phenyl-, Z-[1-(2-phenylvinyl)]-3-phenyl-, and 4,5,6,7-tetrahydroindole, and 2,4-diphenyl-3,3-dimethyl-5-hydroxypyrroline have been obtained from the reaction of ketoximes with phenylacetylene, catalyzed by KOH-DMSO.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 485–488, April, 1992. 相似文献
169.
170.
Noncatalytic Regio- and Stereoselective Addition of Secondary Phosphines to Cyanoacetylenic Alcohols
S. N. Arbuzova S. I. Shaikhutdinova N. K. Gusarov M. V. Nikitin A. G. Mal’kina B. G. Sukhov M. V. Bogdanova B. A. Trofimov 《Russian Journal of General Chemistry》2005,75(4):514-517
Secondary phosphines regio- and stereoselectively add to 4-hydroxy-4-methyl-2-pentynenitrile, a typical and available representative of cyanoacetylenic alcohols, without catalyst at room temperature (THF, 3 h) to form (Z)-3-[dialkyl(aryl) phosphino]-4-hydroxy-4-methyl-2-pentenenitriles in 80–85% yields. These compounds relate to a new class of functionalyzed phosphines, promising ligands for the design of metal-complex catalysts.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 552–555.Original Russian Text Copyright © 2005 by Arbuzova, Shaikhutdinova, Gusarov, Nikitin, Mal’kina, Sukhov, Bogdanova, Trofimov. 相似文献