Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.author | 남원우 | * |
dc.contributor.author | 김진흥 | * |
dc.date.accessioned | 2017-01-18T02:01:27Z | - |
dc.date.available | 2017-01-18T02:01:27Z | - |
dc.date.issued | 2007 | * |
dc.identifier.issn | 0027-8424 | * |
dc.identifier.other | OAK-4464 | * |
dc.identifier.uri | https://dspace.ewha.ac.kr/handle/2015.oak/233935 | - |
dc.description.abstract | The reactivities of mononuclear nonheme iron(IV)-oxo complexes bearing different axial ligands, [Fe IV(O)(TMC)(X)] n+ [where TMC is 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane and X is NCCH 3 (1-NCCH 3), CF 3COO- (1-OOCCF 3), or N 3 - (1-N 3)], and [Fe IV(O)(TMCS)] + (1′-SR) (where TMCS is 1-mercaptoethyl-4,8,11-trimethyl-1,4, 8,11-tetraazacyclotetradecane), have been investigated with respect to oxo-transfer to PPh 3 and hydrogen atom abstraction from phenol O - H and alkylaromatic C - H bonds. These reactivities were significantly affected by the identity of the axial ligands, but the reactivity trends differed markedly. In the oxidation of PPh3, the reactivity order of 1-NCCH 3 > 1-OOCCF 3 > 1-N 3 > 1′-SR was observed, reflecting a decrease in the electrophilicity of iron(IV)-oxo unit upon replacement of CH 3CN with an anionic axial ligand. Surprisingly, the reactivity order was inverted in the oxidation of alkylaromatic C - H and phenol O - H bonds, i.e., 1′-SR > 1-N 3 > 1-OOCCF 3 > 1-NCCH 3. Furthermore, a good correlation was observed between the reactivities of iron(IV)-oxo species in H atom abstraction reactions and their reduction potentials, E p,c, with the most reactive 1′-SR complex exhibiting the lowest potential. In other words, the more electron-donating the axial ligand is, the more reactive the iron(IV)-oxo species becomes in H atom abstraction. Quantum mechanical calculations show that a two-state reactivity model applies to this series of complexes, in which a triplet ground state and a nearby quintet excited-state both contribute to the reactivity of the complexes. The inverted reactivity order in H atom abstraction can be rationalized by a decreased triplet-quintet gap with the more electron-donating axial ligand, which increases the contribution of the much more reactive quintet state and enhances the overall reactivity. © 2007 by The National Academy of Sciences of the USA. | * |
dc.language | English | * |
dc.title | Axial ligand tuning of a nonheme iron(IV)-oxo unit for hydrogen atom abstraction | * |
dc.type | Article | * |
dc.relation.issue | 49 | * |
dc.relation.volume | 104 | * |
dc.relation.index | SCI | * |
dc.relation.index | SCIE | * |
dc.relation.index | SCOPUS | * |
dc.relation.startpage | 19181 | * |
dc.relation.lastpage | 19186 | * |
dc.relation.journaltitle | Proceedings of the National Academy of Sciences of the United States of America | * |
dc.identifier.doi | 10.1073/pnas.0709471104 | * |
dc.identifier.wosid | WOS:000251525800006 | * |
dc.identifier.scopusid | 2-s2.0-37649000653 | * |
dc.author.google | Sastri C.V. | * |
dc.author.google | Lee J. | * |
dc.author.google | Oh K. | * |
dc.author.google | Yoon J.L. | * |
dc.author.google | Jackson T.A. | * |
dc.author.google | Ray K. | * |
dc.author.google | Hirao H. | * |
dc.author.google | Shin W. | * |
dc.author.google | Halfen J.A. | * |
dc.author.google | Kim J. | * |
dc.author.google | Que Jr. L. | * |
dc.author.google | Shaik S. | * |
dc.author.google | Nam W. | * |
dc.contributor.scopusid | 남원우(7006569723) | * |
dc.contributor.scopusid | 김진흥(8580015800) | * |
dc.date.modifydate | 20240116111857 | * |