A diiron complex mediates an intramolecular aliphatic hydroxylation by various oxygen donors

In the presence of hydrogen peroxide, m-chloroperbenzoic acid or an iodosyl arene, the tert-butyl group of the ligand H (L–t-Bu) in the complex [Fe2(L–t-Bu)(mpdp)]^2+ is quantitatively hydroxylated to a butanolate terminally bound to one iron in [Fe2(L–t-Bu – H + O)(mpdp)]^2+, and mass spectrometry experiments indicate that the reaction proceeds according to different mechanisms.