54469-44-2Relevant academic research and scientific papers
KINETICS OF THE REACTION OF PIPERAZINE WITH 1-METHOXY-2,3-EPOXYPROPANE
Mislyuk, O. A.,Shibaev, V. I.,V'yunov, K. A.,Ginak, A. I.
, p. 2000 - 2003 (2007/10/02)
The quantitative relationships governing the formation of N-alkyl and N,N'-dialkylpiperazines were studied.An increase in the yield of the N-alkylpiperazines can be achieved by increasing the temperature and reducing the concentration of the α-oxide in the reaction mass.Comparison of the two investigated reactions indicates that a push-pull mechanism involving two molecules of the reagents and a solvent molecule is realized.
KINETICS OF THE REACTION OF PIPERAZINE WITH 1-R-2,3-EPOXYPROPANES
Mislyuk, O. A.,Shibaev, V. I.,V'yunov, K. A.
, p. 2247 - 2252 (2007/10/02)
The kinetics of the formation of N-alkyl- and N,N'-dialkylpiperazines from piperazine and 1-R-2,3-epoxypropanes were studied.The effect of substituents in the α-oxide on the rate constant for the formation of the N-alkylpiperazine is described by the Taft equation.An isokinetic relationship is fulfilled for the α-oxides with alkoxyl substituents.The features of the relationship are discussed on the basis of a reaction mechanism involving the formation of donor-acceptor complexes.
SYNTHESIS OF MONO- AND BIS(HYDROXYALKYL)PIPERAZINES.
Mislyuk,Shibaev,Davidenkov,V'yunov,Ginak
, p. 1982 - 1983 (2007/10/02)
The known methods for production of mono- and bis(hydroxyalkyl)piperazines are based on the reaction of ethylene oxide with unsubstituted piperazine, but the connection between alkylation of piperazine and the side reaction of oligomerization of alpha -oxides under the influence of catalytic amounts of piperazine has still not been clarified. The interaction of piperazine with substituted alpha -oxides has not been studied at all. We showed with reference to the reactions of piperazine with substituted alpha -oxides that opening of the oxirane ring proceeds exclusively with formation of mono- (I-IV) and N,N prime -bis(hydroxyalkyl)piperazines (V-VIII) in yields of 85-95% calculated on the alpha -oxide. The authors show that the two molecules of the asymmetric alpha -oxide add on exclusively at the nitrogen atoms of the heterocycle, and that oligomerization of the alpha -oxide and addition of its second molecule at the hydroxyl groups of mono(hydroxyalkyl)piperazines (I-IV) make no appreciable contribution. The presence of free hydroxyl groups in compounds (I-VIII) offers possibilities of chemical bonding in epoxy compositions.
KINETICS OF THE REACTION OF PIPERAZINE WITH GYCIDYL METHYL ETHER.
Mislyuk,Shibaev,Davidenkov,V'yunov,Ginak
, p. 1967 - 1968 (2007/10/02)
The authors studied quantitative relationships of interaction of piperazine with a substituted alpha -oxide in order to suggest of raising the selectivity of formation of N-hydroxyalkyl- and N,N prime -bis(hydroxyalkyl)piperazines. Kinetic study of the process suggests two routes for its optimization: The N-(hydroxyalkyl)piperazine yield can be raised by increasing the piperazine concentration in the reaction mass, or by raising the reaction temperature, as the rate of N-(hydroxyalkyl)piperazine (III) formation increases more rapidly with rise of temperature than the rate of N,N prime -bis(hydroxyalkyl)piperazine (IV) formation.
