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dc.contributor.author엄익환-
dc.date.accessioned2016-08-28T12:08:26Z-
dc.date.available2016-08-28T12:08:26Z-
dc.date.issued2012-
dc.identifier.issn0253-2964-
dc.identifier.otherOAK-8825-
dc.identifier.urihttps://dspace.ewha.ac.kr/handle/2015.oak/222683-
dc.description.abstractSecond-order rate constants (kN) have been measured spectrophotometrically for the reactions of benzyl 2- pyridyl carbonate 7 and t-butyl 2-pyridyl carbonate 8 with a series of alicyclic secondary amines in l 2O at 25.0 ° C. Substrate 8 is less reactive than 7. Steric hindrance exerted by the bulky t-Bu group of 8 has been suggested to be responsible for the decreased reactivity. The Brønsted-type plots for the reactions of 7 and 8 are linear with ß nuc = 0.49 and 0.44, respectively, which is typical for reactions reported previously to proceed through a concerted mechanism. Aminolyses of 7 and 8 were expected to proceed through a zwitterionic tetrahedral intermediate T± , which would be stabilized through an intramolecular H-bonding interaction. However, the kinetic results suggest that the reactions proceed through a concerted mechanism. The H-bonding interaction in T± has been suggested to accelerate the rate of leaving-group expulsion from T± . Another factor that might accelerate expulsion of the leaving group is the "push" provided by the RO group in T± through resonance interactions. Thus, it has been concluded that the enhanced nucleofugality through the H-bonding interaction and the "push" provided by the RO group forces the reactions to proceed through a concerted mechanism. Copyright © 2005 KCSNET.-
dc.languageEnglish-
dc.titleKinetics and reaction mechanism of aminolyses of benzyl 2-pyridyl carbonate and t-butyl 2-pyridyl carbonate: Effect of nonleaving group on reactivity and reaction mechanism-
dc.typeArticle-
dc.relation.issue5-
dc.relation.volume33-
dc.relation.indexSCI-
dc.relation.indexSCIE-
dc.relation.indexSCOPUS-
dc.relation.indexKCI-
dc.relation.startpage1551-
dc.relation.lastpage1555-
dc.relation.journaltitleBulletin of the Korean Chemical Society-
dc.identifier.doi10.5012/bkcs.2012.33.5.1551-
dc.identifier.wosidWOS:000304432100021-
dc.identifier.scopusid2-s2.0-84861391171-
dc.author.googleKang J.-S.-
dc.author.googleLee J.-I.-
dc.author.googleUm I.-H.-
dc.contributor.scopusid엄익환(7006725706;6506759437)-
dc.date.modifydate20230411105538-
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자연과학대학 > 화학·나노과학전공 > Journal papers
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