Oxygen Activation and Intramolecular C–H Bond Activation by an Amidate-Bridged Diiron(II) Complex

A diiron(II) complex containing two μ-1,3-(κN:κO)-amidate linkages has been synthesized using the 2,2′,2′′-tris(isobutyrylamido)triphenylamine (H3LiPr) ligand. The resulting diiron complex, 1, reacts with dioxygen (or iodosylbenzene) to effect intramolecular C–H bond activation at the methine position of the ligand isopropyl group. The ligand-activated product, 2, has been isolated and characterized by a variety of methods including X-ray crystallography. Electrospray ionization mass spectroscopy of 2 prepared from18O2 was used to confirm that the oxygen atom incorporated into the ligand framework is derived from molecular oxygen.