Visible-light photolysis of corrole-manganese(IV) nitrites to generate corrole-manganese(V)-oxo complexes

Photolysis of highly photo-labile corrole-manganese(IV) nitrites by visible light was studied in three corrole systems with different electronic environments. As observed in all three systems, homolytic cleavage of O-N bond of nitrite ligand resulted in one-electron photo-oxidation to generate manganese(V)-oxo corroles, as determined by their distinct UV-vis spectra and kinetic behaviors. The spectral and kinetic results are rationalized by a multiple oxidation model, where the electron-demand Mn-v-oxo species may serve as direct two-electron oxidant for oxygen atom transfer reactions and less electron-demand systems undergo a disproportionation reaction to form a putative manganese(VI)-oxo corrole as the true oxidant. (C) 2017 Elsevier B.V. All rights reserved.