Generation of an Isolable, Monomeric Manganese(V)–Oxo Complex from O₂ and Visible Light

Abstract

The direct conversion of a Mn^III complex [(TBP₈Cz)­Mn^III (<b>1</b>)] to a Mn^V–oxo complex [(TBP₈Cz)­Mn^V(O) (<b>2</b>)] with O₂ and visible light is reported. Complex <b>1</b> is also shown to function as an active photocatalyst for the oxidation of PPh₃ to OPPh₃. Mechanistic studies indicate that the photogeneration of <b>2</b> does not involve singlet oxygen but rather likely occurs via a free-radical mechanism upon photoactivation of <b>1</b>