Full metadata record
DC Field | Value | Language |
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dc.contributor.author | 엄익환 | - |
dc.date.accessioned | 2016-08-28T11:08:01Z | - |
dc.date.available | 2016-08-28T11:08:01Z | - |
dc.date.issued | 2006 | - |
dc.identifier.issn | 0947-6539 | - |
dc.identifier.other | OAK-3144 | - |
dc.identifier.uri | https://dspace.ewha.ac.kr/handle/2015.oak/219666 | - |
dc.description.abstract | Second-order rate constants (kN) have been determined spectrophotometrically for the reactions of 2,4-di-nitrophenyl X-substituted benzoates (1a-f) and Y-substituted phenyl benzoates (2a-h) with a series of alicyclic secondary amines in MeCN at 25.0 ± 0.1°C. The kN values are only slightly larger in MeCN than in H2O, although the amines studied are approximately 8 pKa units more basic in the aprotic solvent than in H2O. The Yukawa-Tsuno plot for the aminolysis of 1a-f is linear, indicating that the electronic nature of the substituent X in the nonleaving group does not affect the ratedetermining step (RDS) or reaction mechanism. The Hammett correlation with a constants also exhibits good linearity with a large slope (ρY = 3.54) for the reactions of 2a-h with piperidine, implying that the leaving-group departure occurs at the rate-determining step. Aminolysis of 2,4-dinitrophenyl benzoate (1e) results in a linear Brønsted-type plot with a βnuc value of 0.40, suggesting that bond formation between the attacking amine and the carbonyl carbon atom of le is little advanced in the transition state (TS). A concerted mechanism is proposed for the aminolysis of 1a-f in MeCN. The medium change from H2O to MeCN appears to force the reaction to proceed concertedly by decreasing the stability of the zwitterionic tetrahedral intermediate (T ±) in aprotic solvent. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA. | - |
dc.language | English | - |
dc.title | Aminolysis of 2,4-dinitrophenyl X-substituted benzoates and Y-substituted phenyl benzoates in MeCN: Effect of the reaction medium on rate and mechanism | - |
dc.type | Article | - |
dc.relation.issue | 4 | - |
dc.relation.volume | 12 | - |
dc.relation.index | SCI | - |
dc.relation.index | SCIE | - |
dc.relation.index | SCOPUS | - |
dc.relation.startpage | 1237 | - |
dc.relation.lastpage | 1243 | - |
dc.relation.journaltitle | Chemistry - A European Journal | - |
dc.identifier.doi | 10.1002/chem.200500647 | - |
dc.identifier.wosid | WOS:000234945400027 | - |
dc.identifier.scopusid | 2-s2.0-31344471493 | - |
dc.author.google | Um I.-H. | - |
dc.author.google | Jeon S.-E. | - |
dc.author.google | Seok J.-A. | - |
dc.contributor.scopusid | 엄익환(7006725706;6506759437) | - |
dc.date.modifydate | 20230411105538 | - |