Full metadata record
DC Field | Value | Language |
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dc.contributor.author | 엄익환 | - |
dc.date.accessioned | 2016-12-06T02:12:26Z | - |
dc.date.available | 2016-12-06T02:12:26Z | - |
dc.date.issued | 2008 | - |
dc.identifier.issn | 0947-6539 | - |
dc.identifier.other | OAK-5025 | - |
dc.identifier.uri | https://dspace.ewha.ac.kr/handle/2015.oak/233020 | - |
dc.description.abstract | A kinetic study is reported for alkaline hydrolysis of X-substituted phenyl diphenylphosphinates (1 a-i). The Brønsted-type plot for the reactions of 1 a-i is linear over 4.5 pK(a) units with beta(lg)=-0.49, a typical beta(lg) value for reactions which proceed through a concerted mechanism. The Hammett plots correlated with sigma(o) and sigma(-) constants are linear but exhibit many scattered points, while the corresponding Yukawa-Tsuno plot results in excellent linear correlation with rho=1.42 and r=0.35. The r value of 0.35 implies that leaving-group departure is partially advanced at the rate-determining step (RDS). A stepwise mechanism, in which departure of the leaving group from an addition intermediate occurs in the RDS, is excluded since the incoming HO(-) ion is much more basic and a poorer nucleofuge than the leaving aryloxide. A dissociative (D(N) + A(N)) mechanism is also ruled out on the basis of the small beta(lg) value. As the substituent X in the leaving group changes from H to 4-NO(2) and 3,4-(NO(2))(2), DeltaH++ decreases from 11.3 kcal mol(-1) to 9.7 and 8.7 kcal mol(-1), respectively, while DeltaS++ varies from -22.6 cal mol(-1) K(-1) to -21.4 and -20.2 cal mol(-1) K(-1), respectively. Analysis of LFERs combined with the activation parameters assigns a concerted mechanism to the current alkaline hydrolysis of 1 a-i. | - |
dc.language | English | - |
dc.title | Analysis of linear free-energy relationships combined with activation parameters assigns a concerted mechanism to alkaline hydrolysis of x-substituted phenyl diphenylphosphinates. | - |
dc.type | Article | - |
dc.relation.issue | 24 | - |
dc.relation.volume | 14 | - |
dc.relation.index | SCI | - |
dc.relation.index | SCIE | - |
dc.relation.index | SCOPUS | - |
dc.relation.startpage | 7324 | - |
dc.relation.lastpage | 7330 | - |
dc.relation.journaltitle | Chemistry (Weinheim an der Bergstrasse, Germany) | - |
dc.identifier.doi | 10.1002/chem.200800553 | - |
dc.identifier.wosid | WOS:000258801500026 | - |
dc.identifier.scopusid | 2-s2.0-53049097319 | - |
dc.author.google | Um I.H. | - |
dc.author.google | Han J.Y. | - |
dc.author.google | Hwang S.J. | - |
dc.contributor.scopusid | 엄익환(7006725706;6506759437) | - |
dc.date.modifydate | 20230411105538 | - |