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dc.contributor.author남원우*
dc.contributor.author이용민*
dc.date.accessioned2016-08-28T10:08:30Z-
dc.date.available2016-08-28T10:08:30Z-
dc.date.issued2012*
dc.identifier.issn0002-7863*
dc.identifier.otherOAK-9016*
dc.identifier.urihttps://dspace.ewha.ac.kr/handle/2015.oak/222845-
dc.description.abstract[Fe IV=O(TBC)(CH 3CN)] 2+ (TBC = 1,4,8,11-tetrabenzyl-1,4,8,11-tetraazacyclotetradecane) is characterized, and its reactivity differences relative to [Fe IV=O(TMC)(CH 3CN)] 2+ (TMC = 1,4,8,11-tetramethyl-1,4,8,11- tetraazacyclotetradecane) are evaluated in hydrogen atom (H-atom) abstraction and oxo-transfer reactions. Structural differences are defined using X-ray absorption spectroscopy and correlated to reactivities using density functional theory. The S = 1 ground states are highly similar and result in large activation barriers (∼25 kcal/mol) due to steric interactions between the cyclam chelate and the substrate (e.g., ethylbenzene) associated with the equatorial π-attack required by this spin state. Conversely, H-atom abstraction reactivity on an S = 2 surface allows for a σ-attack with an axial substrate approach. This results in decreased steric interactions with the cyclam and a lower barrier (∼9 kcal/mol). For [Fe IV=O(TBC) (CH 3CN)] 2+, the S = 2 excited state in the reactant is lower in energy and therefore more accessible at the transition state due to a weaker ligand field associated with the steric interactions of the benzyl substituents with the trans-axial ligand. This study is further extended to the oxo-transfer reaction, which is a two-electron process requiring both σ- and π-electron transfer and thus a nonlinear transition state. In oxo-transfer, the S = 2 has a lower barrier due to sequential vs concerted (S = 1) two electron transfer which gives a high-spin ferric intermediate at the transition state. The [Fe IV=O(TBC)(CH 3CN)] 2+ complex is more distorted at the transition state, with the iron farther out of the equatorial plane due to the steric interaction of the benzyl groups with the trans-axial ligand. This allows for better orbital overlap with the substrate, a lower barrier, and an increased rate of oxo-transfer. © 2012 American Chemical Society.*
dc.languageEnglish*
dc.title[Fe IV=O(TBC)(CH 3CN)] 2+: Comparative reactivity of iron(IV)-oxo species with constrained equatorial cyclam ligation*
dc.typeArticle*
dc.relation.issue28*
dc.relation.volume134*
dc.relation.indexSCI*
dc.relation.indexSCIE*
dc.relation.indexSCOPUS*
dc.relation.startpage11791*
dc.relation.lastpage11806*
dc.relation.journaltitleJournal of the American Chemical Society*
dc.identifier.doi10.1021/ja3046298*
dc.identifier.wosidWOS:000306457900072*
dc.identifier.scopusid2-s2.0-84863946732*
dc.author.googleWilson S.A.*
dc.author.googleChen J.*
dc.author.googleHong S.*
dc.author.googleLee Y.-M.*
dc.author.googleClemancey M.*
dc.author.googleGarcia-Serres R.*
dc.author.googleNomura T.*
dc.author.googleOgura T.*
dc.author.googleLatour J.-M.*
dc.author.googleHedman B.*
dc.author.googleHodgson K.O.*
dc.author.googleNam W.*
dc.author.googleSolomon E.I.*
dc.contributor.scopusid남원우(7006569723)*
dc.contributor.scopusid이용민(36546331100;35233855500;57192113229)*
dc.date.modifydate20240130092654*
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자연과학대학 > 화학·나노과학전공 > Journal papers
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