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M. G. Voronkov V. I. Rakhlin S. N. Adamovich L. P. Petukhov R. G. Mirskov N. K. Yarosh A. L. Kuznetsov M. V. Sigalov 《Russian Chemical Bulletin》1986,35(4):819-821
Conclusions 1-Hydrosilatrane does not react with monosubstituted ethylenes (or acetylenes) either in the presence of platinum or rhodium complexes or upon initiation of the reactions using organic peroxides, UV irradiation, or thermal methods. By contrast, 2-methyl-6-ethyl-1,3-dioxa-6-aza-2-silacyclooctane readily takes part in hydrosilylation of the indicated unsaturated compounds when Rhacac (CO)2 is present.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khirnicheskaya, No. 4, pp. 899–901, April, 1986. 相似文献
3.
S. E. Korostova S. G. Shevchenko M. V. Sigalov N. I. Golovanova 《Chemistry of Heterocyclic Compounds》1991,27(4):363-365
The reaction of 1-methyl-2-acetylpyrrole oxime with acetylene at atmospheric and increased pressure can be catalyzed by KOH-DMSO superbase to give 1-methyl-2-(2-pyrrolyl)pyrrole, N-vinyl-2-[1-methyl(2-pyrrolyl)]pyrrole, and the reaction intermediate methyl-2-(1-methylpyrrolyl)-O-vinyloxime.See [1] for Communication 44.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 460–463, April, 1991. 相似文献
4.
A. B. Trofimov B. A. Trofimov N. M. Vitkovskaya M. V. Sigalov 《Chemistry of Heterocyclic Compounds》1991,27(6):583-590
The electron and conformational structures, as well as the internal rotation, of 2-(2-furyl)pyrrole and its -protonated forms were studied by the MNDO method with complete optimization of the geometry. In conformity with the experiments (PMR), the two delocalized cations with a cis orientation of the heteroatoms that are formed as a result of protonation of the pyrrole or furan ring have the greatest and virtually equal stabilities (H=738.7 and 740.6 kJ/mole).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 746–753, June, 1991. 相似文献
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S. E. Korostova B. A. Trofimov L. N. Sobenina A. I. Mikhaleva M. V. Sigalov 《Chemistry of Heterocyclic Compounds》1982,18(10):1043-1045
2-(1-Naphthyl)- and 2-(2-naphthyl)pyrroles and their 1-vinyl derivatives were synthesized in 22–64% yields by the reaction of 1- and 2-acetylnaphthalene oximes with acetylene at both atmospheric pressure and elevated pressures in an alkali metal hydroxide-dimethyl sulfoxide system.See [1] for communication 22.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1351–1353, October, 1982. 相似文献
7.
B. A. Trofimov M. V. Sigalov V. M. Bzhezovskii G. A. Kalabin A. I. Mikhaleva A. N. Vasil'ev 《Chemistry of Heterocyclic Compounds》1978,14(3):285-289
The 13C NMR spectra of eight 2-alkyl- and 2,3-dialkyl-1-vinylpyrroles were studied. The 13C chemical shifts of all of the carbon atoms of the ring and the vinyl group depend substantially on the position and structure of the alkyl substituent. As the branched character of the alkyl group in the 2 position increases, the signal of the -carbon atom of the vinyl group is shifted to weak field due to weakening of the p- conjugation in the N-vinyl group because of disruption of its coplanarity with the pyrrole ring. The conjugation between the double bond and the pyrrole system involves competition for possession of the p electrons of the nitrogen atom.See [16] for communication II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 350–354, March, 1978. 相似文献
8.
Eve Kozari Dr. Mark Sigalov Dr. Dina Pines Dr. Benjamin P. Fingerhut Prof. Dr. Ehud Pines 《Chemphyschem》2021,22(8):716-725
Infrared (IR) absorption in the 1000–3700 cm−1 range and 1H NMR spectroscopy reveal the existence of an asymmetric protonated water trimer, H7+O3, in acetonitrile. The core H7+O3 motif persists in larger protonated water clusters in acetonitrile up to at least 8 water molecules. Quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) simulations reveal irreversible proton transport promoted by propagating the asymmetric H7+O3 structure in solution. The QM/MM calculations allow for the successful simulation of the measured IR absorption spectra of H7+O3 in the OH stretch region, which reaffirms the assignment of the H7+O3 spectra to a hybrid-complex structure: a protonated water dimer strongly hydrogen-bonded to a third water molecule with the proton exchanging between the two possible shared-proton Zundel-like centers. The H7+O3 structure lends itself to promoting irreversible proton transport in presence of even one additional water molecule. We demonstrate how continuously evolving H7+O3 structures may support proton transport within larger water solvates. 相似文献
9.
The formation of heterophase polymers via phase separation in the course of curing reaction in a blend of a thermosetting oligomer with a rubber modifier is considered. The interference of thermodynamic and kinetic factors that define the morphology of the material being formed is discussed. The need for a kinetic theory of cure-induced phase separation is established, and an approach of this kind is proposed. On the basis of this approach a simple quantitative criterion of deflection of the phase-separating system from the thermodynamic equilibrium is given. 相似文献
10.
The synthesis of 2-methyl-3-(2-propenyl)pyrrole () and E- and Z-2-methyl-3-(1-propenyl)pyrroles () via the reaction of 3-butenyl methyl ketoxime () with acetylene in the KOH-DMSO system is reported. 相似文献