Teruyuki Komatsu and Kaoru Sano
Intramolecular N-imidazole coordinated [5,10,15,20-tetrakis(α,α,α,α-o-pivaloyloxynaphthyl)porphinato]iron(II) forms a stable dioxygen adduct in toluene at 25 °C; the sterically regulated coordination of the axial base leads to the low electron donation from the central iron to the bound O2.