Distinct Reactivity Differences of Metal Oxo and Its Corresponding Hydroxo Moieties in Oxidations: Implications from a Manganese(IV) Complex Having Dihydroxide Ligand

School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, China.
Angewandte Chemie International Edition (Impact Factor: 11.26). 08/2011; 50(32):7321-4. DOI: 10.1002/anie.201100588
Source: PubMed


The M n+-OH moiety in a manganese(IV) complex has more powerful electron-transfer capability than its corresponding M n+=O moiety. An M n+=O moiety can abstract hydrogen from a substrate, then rebind the OH group from its reduced M (n-1)+-OH form to the substrate radical. In contrast, the active center with an M n+-OH cannot perform similar rebound from its reduced M (n-1)+-OH 2 group (see scheme; HAT=hydrogen abstraction).

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