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Yu. L. Frolov V. K. Voronov N. M. Deriglazov L. V. Belousova N. M. Vitkovskaya S. M. Tyrina G. G. Skvortsova 《Chemistry of Heterocyclic Compounds》1972,8(1):89-94
The PMR, Raman, and UV absorption spectra of 2-hydroxypyridine and its vinyl derivatives were investigated. Their electrochemical reduction was studied, and a quantum-chemical analysis of them was performed. It was concluded that the structure of 2-hydroxypyridine in proton-donor solvents is mesomeric, and its wave function, to a first approximation, is a linear combination of the wave functions of the 2-pyridone and zwitterion models. The contribution of the wave functions of each of the models depends substantially on the concentration of the solution and the nature of the solvent. An assumption was made regarding the presence of dynamic conjugation between the vinyl group and the ring in vinyl derivatives of 2-hydroxypyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 95–102 January, 1972. 相似文献
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Methylthio- (MTE) and bis-methylthioethyne (BMTE) molecules are calculated by the SCF MO method (geometry optimization, basis
set 6–31G*/MP2). The calculated internal rotation barriers of methyl groups are 7.12 kJ/lmole for MTE and 12.86 kJ/mole for
BMTE (both groups are simultaneously rotated). The s-gosh-orientation of the thiomethyl fragments corresponds to a stable
conformation of BMTE. The estimated values of the s-cis- and s-trans-barriers of mutual rotation of SCH3 groups about the axis of the C≡C bond are 13.61 and 12.54 kJ/mole, respectively. Conformationally sensitive MOs and vibration
frequencies are established. An analysis of the experimental IR absorption and Raman spectra and the calculated vibrational
spectrum makes it possible to conclude that in the liquid phase the BMTE molecules also have an s-gosh-conformation.
Translated fromZhumal Strukturnoi Khimii, Vol. 39, No. 4, pp. 602–609, July–August, 1998. 相似文献
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K. A. Frolov V. V. Dotsenko S. G. Krivokolysko V. P. Litvinov 《Russian Chemical Bulletin》2005,54(9):2226-2228
Reactions of (Z)-5-benzylidene-2-thiohydantoin with formaldehyde and primary aromatic amines afforded novel derivatives of imidazo[2,1-b][1,3,5]thiadiazine in 50–69% yields.
Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2158–2160, September, 2005. 相似文献
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N. N. Chipanina A. M. Shulunova T. I. Yushmanova L. I. Volkova V. A. Lopyrev Yu. L. Frolov 《Russian Chemical Bulletin》1987,36(10):2182-2183
Conclusions An IR spectroscopic study showed that the C=0 values in the spectra of N,N-dimethylhydrazides of aromatic acids, RCONHN(Me)2, correlate linearly with a regression equation obtained for the unsubstituted hydrazides of aromatic acids, RCONHNH2. This dependence differs significantly from that for N-methyl-N-aroylhydrazines, in which ,-conjugation in the RC(O)N group is more pronounced.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2353–2355, October, 1987. 相似文献
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