Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.author | 엄익환 | - |
dc.date.accessioned | 2016-08-27T04:08:54Z | - |
dc.date.available | 2016-08-27T04:08:54Z | - |
dc.date.issued | 2014 | - |
dc.identifier.issn | 0253-2964 | - |
dc.identifier.issn | 1229-5949 | - |
dc.identifier.other | OAK-11669 | - |
dc.identifier.uri | https://dspace.ewha.ac.kr/handle/2015.oak/216869 | - |
dc.description.abstract | Second-order rate constants (k(N)) have been measured spectrophotometrically for the reactions of phenyl 2-pyridyl carbonate(6) with a series of cyclic secondary amines in MeCN at 25.0 +/- 0.1 degrees C. The Bronsted-type plot for the reaction of 6 is linear with beta(nuc) = 0.54, which is typical for reactions reported previously to proceed through a concerted mechanism. Substrate 6 is over 10(3) times more reactive than 2-pyridyl benzoate (5), although the reactions of 6 and 5 proceed through the same mechanism. A combination of steric hindrance, inductive effect and resonance contribution is responsible for the kinetic results. The reactions of 6 and 5 proceed through a cyclic transition state (TS) in which H-bonding interactions increase the nucleofugality of the leaving group (i.e., 2-pyridiniumoxide). The enhanced nucleofugality forces the reactions of 6 and 5 to proceed through a concerted mechanism. In contrast, the corresponding reaction of 4-nitrophenyl 2-pyridyl carbonate (7) proceeds through a stepwise mechanism with quantitative liberation of 4-nitrophenoxide ion as the leaving group, indicating that replacement of the 4-nitrophenoxy group in 7 by the PhO group in 6 changes the reaction mechanism (i.e., from a stepwise mechanism to a concerted pathway) as well as the leaving group (i.e., from 4-nitrophenoxide to 2-pyridiniumoxide). The strong electron-withdrawing ability of the 4-nitrophenoxy group in 7 inhibits formation of a H-bonded cyclic TS. The presence or absence of a H-bonded cyclic TS governs the reaction mechanism (i.e., a concerted or stepwise mechanism) as well as the leaving group (i.e., 2-pyridiniumoxide or 4-nitrophenoxide). | - |
dc.language | English | - |
dc.publisher | KOREAN CHEMICAL SOC | - |
dc.subject | Aminolysis | - |
dc.subject | Steric hindrance | - |
dc.subject | Inductive effect | - |
dc.subject | Resonance contribution | - |
dc.subject | H-bonding interaction | - |
dc.title | Kinetic Study on Aminolysis of Phenyl 2-Pyridyl Carbonate in Acetonitrile: Effect of Intramolecular H-bonding Interaction on Reactivity and Reaction Mechanism | - |
dc.type | Article | - |
dc.relation.issue | 7 | - |
dc.relation.volume | 35 | - |
dc.relation.index | SCIE | - |
dc.relation.index | SCOPUS | - |
dc.relation.index | KCI | - |
dc.relation.startpage | 2081 | - |
dc.relation.lastpage | 2085 | - |
dc.relation.journaltitle | BULLETIN OF THE KOREAN CHEMICAL SOCIETY | - |
dc.identifier.doi | 10.5012/bkcs.2014.35.7.2081 | - |
dc.identifier.wosid | WOS:000339642700031 | - |
dc.identifier.scopusid | 2-s2.0-84940286547 | - |
dc.author.google | Song, Ji-Hyun | - |
dc.author.google | Lee, Jae-In | - |
dc.author.google | Um, Ik-Hwan | - |
dc.contributor.scopusid | 엄익환(7006725706;6506759437) | - |
dc.date.modifydate | 20230411105538 | - |