Photooxidation by a long-lived photoexcited state of a triflic acid-bound Mn(IV)-oxo complex with the highest quantum efficiency

This study reports a long-lived 2 E photoexcited state (τ = 21 µs) of metal-oxo complex composed of only earth-abundant elements, which oxidizes toluene by the two-photon four-electron oxidation process with ∼200% quantum efficiency that is the highest value ever reported.