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dc.contributor.author엄익환-
dc.date.accessioned2017-12-27T16:30:49Z-
dc.date.available2017-12-27T16:30:49Z-
dc.date.issued2017-
dc.identifier.issn0253-2964-
dc.identifier.otherOAK-21513-
dc.identifier.urihttps://dspace.ewha.ac.kr/handle/2015.oak/239374-
dc.description.abstractSecond-order rate constants (kN) for nucleophilic substitution reactions of O-phenyl O-Y-substituted-phenyl thionocarbonates (4a–4k) with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in MeCN at 25.0 ± 0.1°C are reported. The reactivity of 4a–4k decreases as basicity of the leaving group increases except O-2,4-dinitrophenyl O-phenyl thionocarbonate (4a), which is less reactive than O-3,4-dinitrophenyl O-phenyl thionocarbonate (4b) although the former possesses 2 pKa units less basic nucleofuge than the latter. The Brønsted-type plot for the reactions of 4b–4k is linear with βlg = −0.50, a typical βlg value for reactions reported to proceed through a concerted mechanism. The Hammett plot correlated with σY − constants for the reactions of 4b–4k results in a better linear correlation than that correlated with σY o constants. Besides, the Yukawa-Tsuno plot exhibits an excellent linear correlation with ρY = 2.12, r = 0.68 and R2 = 0.990, indicating that a negative charge develops partially on the O atom of the leaving group in the rate-determining step (RDS). Thus, the reactions have been concluded to proceed through a forced concerted mechanism. Effects of steric hindrance on reactivity and reaction mechanism are also discussed in detail. © 2017 Korean Chemical Society, Seoul & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim-
dc.languageEnglish-
dc.publisherWiley Blackwell-
dc.subject1,8-Diazabicyclo[5.4.0]undec-7-ene-
dc.subjectBrønsted-type plot-
dc.subjectForced concerted mechanism-
dc.subjectO-Phenyl O-Y-substituted-phenyl thionocarbonates-
dc.subjectSteric hindrance-
dc.titleKinetic Study on Nucleophilic Substitution Reactions of O-Phenyl O-Y-substituted-Phenyl Thionocarbonates with 1,8-Diazabicyclo[5.4.0]undec-7-ene in Acetonitrile-
dc.typeArticle-
dc.relation.issue10-
dc.relation.volume38-
dc.relation.indexSCOPUS-
dc.relation.indexKCI-
dc.relation.startpage1169-
dc.relation.lastpage1173-
dc.relation.journaltitleBulletin of the Korean Chemical Society-
dc.identifier.doi10.1002/bkcs.11242-
dc.identifier.wosidWOS:000413356700010-
dc.identifier.scopusid2-s2.0-85028917289-
dc.author.googleUm I.-H.-
dc.author.googlePark K.-H.-
dc.contributor.scopusid엄익환(7006725706;6506759437)-
dc.date.modifydate20180104081001-
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자연과학대학 > 화학·나노과학전공 > Journal papers
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