Distinguishing Features of reactions of 2-chloro-and 2,2-dichloro(bromo)vinyl ketones with alkyl-and arylhydrazines
作者:G. V. Bozhenkov、V. A. Savosik、L. I. Larina、L. V. Klyba、E. R. Zhanchipova、A. N. Mirskova、G. G. Levkovskaya
DOI:10.1134/s1070428008070129
日期:2008.7
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 N1-alkyl-N2-(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 H-1 and C-13 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.
Solvatochromism of heteroaromatic compounds: XXVIII. Factors affecting the nonspecific solvatochromic effect in the UV spectra of aromatic nitro compounds in aprotic protophilic solvents
作者:A. I. Vokin、A. M. Shulunova、T. N. Aksamentova、G. V. Bozhenkov、V. K. Turchaninov
DOI:10.1134/s1070363206040189
日期:2006.4
Examination of the UV spectra of a large series of solvatochromic indicators of the general formula 1-X-4-NO2-C6H4 in aprotic solvents confirmed the proportionality between the dipole moments of these compounds in the ground (mu(g)) and first electronically excited ((1)A(1), mu(e)) states: mu(e) = r(mu)mu(g). The coefficient r(mu) was determined by applying the equation of the Bakhshiev-Bilot-Kawski solvatochromism theory both to nonspecifically solvated. molecules and to their H complexes with aprotic protophilic solvents. An anisotropy of the electron redistribution was revealed for low-symmetry 1-substituted 2,4-dinitrobenzenes. The r(mu) value obtained allowed the calculation of the Kamlet-Taft empirical solvatochromic parameter pi* on the basis of generalized characteristics of the solvent.
Synthesis and properties of 2-amino-1-chloroenones
作者:G. V. Bozhenkov、V. A. Savosik、A. N. Mirskova、G. G. Levkovskaya
DOI:10.1134/s1070428007010022
日期:2007.1
Reactions of alkyl-, allyl-, and arylamines and o-aminophenol with 1,2-dichlorovinyl alkyl ketones involve replacement of only one chlorine atom in the beta-position with respect to the carbonyl group with formation of 2-alkylamino-, 2-allylamino-, and 2-arylamino-1-chlorovinyl ketones. Diamines of the aromatic and aliphatic series react with 1,2-dichlorovinyl alkyl ketone molecules to give N,N'-bis(2-acyl-2-chlorovinyl)-substituted diamines.