The oxoiron(IV) complexes of two 6-substituted tris(2-pyridylmethyl)amine ligand derivatives have been generated and characterized with respect to their spectroscopic and reactivity properties. The introduction of an α-substituent maintains the low-spin nature of the oxoiron(IV) unit but weakens the ligand field, as evidenced by red shifts in its characteristic near-IR chromophore. While its hydrogen-atom abstraction ability is only slightly affected, the oxo-transfer reactivity of the oxoiron(IV) center is significantly enhanced relative to that of the parent complex. These results demonstrate that the ligand environment plays a key role in modulating the reactivity of this important biological oxidant.
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Acknowledgement This work was supported by grant GM33162 from the National Institutes of Health to L.Q.
- Nonheme iron intermediates
- Oxoiron(IV) complexes
- Taurine/α-ketoglutarate dioxygenase