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dc.contributor.author엄익환-
dc.date.accessioned2016-08-28T12:08:03Z-
dc.date.available2016-08-28T12:08:03Z-
dc.date.issued2008-
dc.identifier.issn0253-2964-
dc.identifier.otherOAK-5056-
dc.identifier.urihttps://dspace.ewha.ac.kr/handle/2015.oak/220062-
dc.description.abstractSecond-order rate constants (kN) have been measured spectrophotometrically for reactions of 3,4-dinitrophenyl 2-thiophenecarboxylate (2) with a series of alicyclic secondary amines in 80 mol % H2O/20 mol % dimethyl sulfoxide at 25.0 °C. The Brønsted-type plot exhibits a downward curvature for the aminolysis of 2. The curved Brønsted-type plot is similar to that reported for the corresponding reactions of 2,4-dinitrophenyl 2-thiophenecarboxylate (1). The reactions of 1 and 2 have been suggested to proceed through the same mechanism, i.e., through a zwitterionic tetrahedral intermediate (T±) with a change in the rate-determining step. Substrate 2 is less reactive than 1 toward weakly basic amines (e.g., pKa < 10.4) but becomes more reactive as the basicity of amines increases further. Dissection of kN into the microscopic rate constants has revealed that the reaction of 2 results in a smaller k2/k-1 ratio but larger k1 than the corresponding reaction of 1. Steric hindrance exerted by the ortho-nitro group has been suggested to be responsible for the smaller k1 value found for the reactions of 1.-
dc.languageEnglish-
dc.titleAminolysis of 2,4-dinitrophenyl and 3,4-dinitrophenyl 2- thiophenecarboxylates: Effect of ortho-nitro group on reactivity and mechanism-
dc.typeArticle-
dc.relation.issue8-
dc.relation.volume29-
dc.relation.indexSCIE-
dc.relation.indexSCOPUS-
dc.relation.indexKCI-
dc.relation.startpage1459-
dc.relation.lastpage1463-
dc.relation.journaltitleBulletin of the Korean Chemical Society-
dc.identifier.wosidWOS:000259292000007-
dc.identifier.scopusid2-s2.0-50449110073-
dc.author.googleSeo J.-A.-
dc.author.googleChun S.-M.-
dc.author.googleUm I.-H.-
dc.contributor.scopusid엄익환(7006725706;6506759437)-
dc.date.modifydate20170601135413-
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자연과학대학 > 화학·나노과학전공 > Journal papers
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