Article

Valence Tautomerism in a High-Valent Manganese-Oxo Porphyrinoid Complex Induced by a Lewis Acid

Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
Journal of the American Chemical Society (Impact Factor: 11.44). 06/2012; 134(25):10397-400. DOI: 10.1021/ja304609n
Source: PubMed

ABSTRACT Addition of the Lewis acid Zn(2+) to (TBP(8)Cz)Mn(V)(O) induces valence tautomerization, resulting in the formation of [(TBP(8)Cz(+•))Mn(IV)(O)-Zn(2+)]. This new species was characterized by UV-vis, EPR, the Evans method, and (1)H NMR and supported by DFT calculations. Removal of Zn(2+) quantitatively restores the starting material. Electron-transfer and hydrogen-atom-transfer reactions are strongly influenced by the presence of Zn(2+).

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