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101.
G. V. Bozhenkov V. A. Savosik L. I. Larina L. V. Klyba E. R. Zhanchipova A. N. Mirskova G. G. Levkovskaya 《Russian Journal of Organic Chemistry》2008,44(7):1014-1023
2-Chlorovinyl alkyl ketones react with alkylhydrazines to give mixtures of 1-R-3-R′- and 1-R-5-R′-pyrazoles: The 1-R-3-R′-pyrazoles form through the heterocyclization of 2-chlorovinyl ketone alkylhydrazones whereas in the heterocyclization into 1-R-5-R′-pyrazoles N 1-alkyl-N 2-(2-acylvinyl)hydrazines are involved. The regiospecific heterocyclization of 2-chloro-and 2,2-dichlorovinyl ketones with arylhydrazines and also of 2,2-dichloro(bromo)vinyl trifluoromethyl ketones with C alkylhydrazines into pyrazoles and 5-chloro(bromo)-pyrazoles proceeds through a stage of haloenones hydrazones formation. The study of the structure of the obtained 1-alkyl-3(5)-alkylpyrazoles by means of two-dimenaional 1H and 13C NMR spectroscopy and GC-MS method made it possible to assign the proton and carbon signals of isomeric pyrazoles and to establish the diagnostic ions for the pair of 1,3-and 1,5-isomers. 相似文献
102.
103.
V. N. Elokhina A. S. Nakhmanovich L. I. Larina O. V. Shishkin V. N. Baumer V. A. Lopyrev 《Russian Chemical Bulletin》1999,48(8):1516-1518
1-[1-Bromo-2-benzoyl(2-thenoyl)vinyl]-1,1-dimethylhydrazinium bromides were synthesized by the reactions of 1-aroyl-2-bromoacetylenes
withN,N-dimethylhydrazine in acetonitrile at 20°C. The structure of 1-(2-benzoyl-1-bromovinyl)-1,1-dimethylhydrazinium bromide was
established by X-ray diffraction analysis.
Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1536–1538, August, 1999. 相似文献
104.
William F. Doran IV 《Journal of Algebraic Combinatorics》1998,8(3):253-272
This paper gives a new formula for the plethysm of power-sum symmetric functions and Schur symmetric functions with one part. The form of the main result is that for b,
where the sum is over semistandard tableaux T of weight a
b
,
is a root of unity, and maj(T) is a major index like statistic on semistandard tableaux.An Sb-representation, denoted S,b, is defined. In the special case when b, S,b is the Specht module corresponding to . It is shown that the character of S,b on elements of cycle type is
where the sum is over semistandard tableaux T of shape and weight ab. Moreover, the eigenvalues of the action of an element of cycle type acting on S,b are {
}. This generalizes J. Stembridge's result [11] on the eigenvalues of elements of the symmetric group acting on the Specht modules. 相似文献
105.
Igor B. Rozentsveig Galina G. Levkovskaya Gulnur N. Rozentsveig Anna N. Mirskova Leonid B. Krivdin Ludmila I. Larina Aleksandr I. Albanov 《Tetrahedron letters》2005,46(51):8889-8893
The interaction of N-(1-aryl-2,2,2-trichloroethyl)amides of arenesulfonic acids with secondary amines or their salts in the presence of inorganic bases involves the formation of chloroaziridine intermediates. Depending upon the solvent and reagent ratio, the reaction results in N-[1-dialkylamino-2-chloro-2-arylethylidene]-, N-[2-dialkylamino-1-chloro-2-arylethylidene]-, N-[1,2-bis(dialkylamino)-2-arylethylidene]-, and N-(1,2-dioxo-2-arylethene)amides of arenesulfonic acids. 相似文献
106.
G. V. Bozhenkov G. G. Leckovskaya L. I. Larina P. E. Ushakov G. V. Dolgushin A. N. Mirskova 《Russian Journal of Organic Chemistry》2004,40(11):1583-1592
A method of alkyl 1,2-dichlorovinyl ketones preparation from acyl halides and 1,2-dichloroethylene was developed. The configurational equilibrium and electronic structure of alkyl 1,2-dichlorovinyl ketones was investigated by IR, 1H and 13C NMR spectroscopy, by measuring dipole moments, and by quantum-chemical calculations using methods RHF and B3LYP in the basis 6–311++G (d,p). Alkyl 1,2-dichlorovinyl ketones are stable in the Z, s-cis-configuration where the olefin proton is involved into an intramolecular hydrogen bond with the oxygen of the carbonyl group. Reaction of 1,2-dichlorovinyl ketones with alkylhydrazines afforded 1-alkyl-3-alkyl-4-chloropyrazoles. The reaction of alkyl 1,2-dichlorovinyl ketones with 1,1-dimethylhydrazine involved dehydrochlorination and afforded 1,1-dimethylhydrazinium hydrochloride and a mixture of compounds with uncertain structure.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 11, 2004, pp. 1632–1640.Original Russian Text Copyright © 2004 by Bozhenkov, Leckovskaya, Larina, Ushakov, Dolgushin, Mirskova. 相似文献
107.
M. M. Demina P. S. Novopashin G. I. Sarapulova L. I. Larina A. S. Smolin V. S. Fundamenskii A. A. Kashaev A. S. Medvedeva 《Russian Journal of Organic Chemistry》2004,40(12):1804-1809
Reactions of trimethylsilyl azide with 3-trimethylsilyl-2-propynal and 2-propynal were studied. X-Ray analysis of the molecular structure of 4-trimethylsilyl-1H-1,2,3-triazole-5-carbaldehyde showed that the carbonyl group appears in the s-cis conformation with respect to the double C=C bond in the heteroring. The effect of the temperature and polarity of the medium on the ability of 1H-1,2,3-triazole-5-carbaldehyde to undergo dimerization to tricyclic bis-hemiaminals was examined by IR and 1H NMR spectroscopy.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1852–1857.Original Russian Text Copyright © 2004 by Demina, Novopashin, Sarapulova, Larina, Smolin, Fundamenskii, Kashaev, Medvedeva. 相似文献
108.
109.
Richard P. Kent IV 《Proceedings of the American Mathematical Society》2005,133(12):3735-3744
Given a compact orientable -manifold whose boundary is a hyperbolic surface and a simple closed curve in its boundary, every knot in is homotopic to one whose complement admits a complete hyperbolic structure with totally geodesic boundary in which the geodesic representative of is as small as you like.
110.