Multifrequency,multitechnique pulse EPR spectroscopy was employed to unravel the spin Hamiltonian parameters of^(17)O in the[Fe^(Ⅴ)=O]moiety with two different tetraamido macrocyclic ligands(TAMLs),[Fe^(Ⅴ)(O)(TAML-1...Multifrequency,multitechnique pulse EPR spectroscopy was employed to unravel the spin Hamiltonian parameters of^(17)O in the[Fe^(Ⅴ)=O]moiety with two different tetraamido macrocyclic ligands(TAMLs),[Fe^(Ⅴ)(O)(TAML-1)]^(−)(1,H_(4)(TAML-1)=3,4,8,9-tetrahydro-3,3,6,6,9-hexamethyl-1H-1,4,8,11-benzotetraazocyclotridecane-2,5,7,10-(6H,11H)-tetrone)and[Fe^(Ⅴ)(O)(TAML-2)]^(−)(2,H_(4)(TAML-2)=H_(4)[(Me_(2)CNCOCMe_(2)NCO)_(2)CMe_(2)]),to investigate the electronic structure of Fe^(Ⅴ)-oxo species.Although rigorous computational studies on highvalent iron-oxo species have been reported recently,experimental evidence to explicate the electronic structure of Fe^(Ⅴ)-oxo species is sparse.In particular,a complete hyperfine tensor of^(17)O can hardly be detected.Herein,we successfully probed the hyperfine tensor of^(17)O of the Fe^(Ⅴ)-oxo moiety using ENDOR spectroscopy.Hence,the EPR spectroscopic results reported here provide a conclusive experimental basis for elucidating the electronic structure of the Fe^(Ⅴ)-oxo complex.Moreover,the reactivity of the two different complexes is very distinct,and our results may provide insight into how their electronic structure contributes to their reactivity.展开更多
基金supported by the National Research Foundation of Korea(NRF-2017M3D1A1039380 and NRF-2020R1F1A1069151)KBSI grant C1300000 to S.H.K+1 种基金supported by the NRF of Korea through CRI(NRF-2012R1A3A2048842 to W.N.)the Basic Science Research Program(NRF-2020R1I1A1A01074630 to Y.-M.L.).
文摘Multifrequency,multitechnique pulse EPR spectroscopy was employed to unravel the spin Hamiltonian parameters of^(17)O in the[Fe^(Ⅴ)=O]moiety with two different tetraamido macrocyclic ligands(TAMLs),[Fe^(Ⅴ)(O)(TAML-1)]^(−)(1,H_(4)(TAML-1)=3,4,8,9-tetrahydro-3,3,6,6,9-hexamethyl-1H-1,4,8,11-benzotetraazocyclotridecane-2,5,7,10-(6H,11H)-tetrone)and[Fe^(Ⅴ)(O)(TAML-2)]^(−)(2,H_(4)(TAML-2)=H_(4)[(Me_(2)CNCOCMe_(2)NCO)_(2)CMe_(2)]),to investigate the electronic structure of Fe^(Ⅴ)-oxo species.Although rigorous computational studies on highvalent iron-oxo species have been reported recently,experimental evidence to explicate the electronic structure of Fe^(Ⅴ)-oxo species is sparse.In particular,a complete hyperfine tensor of^(17)O can hardly be detected.Herein,we successfully probed the hyperfine tensor of^(17)O of the Fe^(Ⅴ)-oxo moiety using ENDOR spectroscopy.Hence,the EPR spectroscopic results reported here provide a conclusive experimental basis for elucidating the electronic structure of the Fe^(Ⅴ)-oxo complex.Moreover,the reactivity of the two different complexes is very distinct,and our results may provide insight into how their electronic structure contributes to their reactivity.
