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dc.contributor.author엄익환-
dc.contributor.author박종윤-
dc.date.accessioned2016-08-28T10:08:07Z-
dc.date.available2016-08-28T10:08:07Z-
dc.date.issued2013-
dc.identifier.issn0022-3263-
dc.identifier.otherOAK-10190-
dc.identifier.urihttp://dspace.ewha.ac.kr/handle/2015.oak/223804-
dc.description.abstractA kinetic study is reported for the Michael-type reactions of X-substituted β-nitrostyrenes (1a-j) with a series of cyclic secondary amines in MeCN. The plots of pseudo-first-order rate constant kobsd vs [amine] curve upward, indicating that the reactions proceed through catalyzed and uncatalyzed routes. The dissection of kobsd into Kk2 and Kk 3 (i.e., the rate constants for the uncatalyzed and catalyzed routes, respectively) revealed that Kk3 is much larger than Kk2, implying that the reactions proceed mainly through the catalyzed route when [amine] > 0.01 M. Strikingly, the reactivity of β-nitrostyrene (1g) toward piperidine decreases as the reaction temperature increases. Consequently, a negative enthalpy of activation is obtained, indicating that the reaction proceeds through a relatively stable intermediate. The Brønsted-type plots for the reactions of 1g are linear with βnuc = 0.51 and 0.61, and the Hammett plots for the reactions of 1a-j are also linear with ρX = 0.84 and 2.10 for the uncatalyzed and catalyzed routes, respectively. The reactions are concluded to proceed through six-membered cyclic transition states for both the catalyzed and uncatalyzed routes. The effects of the substituent X on reactivity and factors influencing βnuc and ρX obtained in this study are discussed. © 2013 American Chemical Society.-
dc.languageEnglish-
dc.titleKinetic study on michael-type reactions of β-nitrostyrenes with cyclic secondary amines in acetonitrile: Transition-state structures and reaction mechanism deduced from negative enthalpy of activation and analyses of LFERs-
dc.typeArticle-
dc.relation.issue11-
dc.relation.volume78-
dc.relation.indexSCIE-
dc.relation.indexSCOPUS-
dc.relation.startpage5604-
dc.relation.lastpage5610-
dc.relation.journaltitleJournal of Organic Chemistry-
dc.identifier.doi10.1021/jo4007442-
dc.identifier.wosidWOS:000320298700048-
dc.identifier.scopusid2-s2.0-84879290760-
dc.author.googleUm I.-H.-
dc.author.googleKang J.-S.-
dc.author.googlePark J.-Y.-
dc.contributor.scopusid엄익환(7006725706;6506759437)-
dc.contributor.scopusid박종윤(15036487300)-
dc.date.modifydate20180104081001-
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자연과학대학 > 화학·나노과학전공 > Journal papers
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