Biomimetic oxidations at active sites of iron proteins involve peroxides, particularly hydrogen peroxide, which is a powerful and very convenient reagent as it is inexpensive and does not release toxic byproducts. In many cases, however, Mother Nature uses molecular oxygen to carry out large-scale oxidation reactions under particularly attractive conditions. The biomimetic interest of iron complexes of the tris(2-pyridylmethyl)amine series (TPA) can no longer be proven. We have prepared various - substituted TPA-based ligands with the idea of modulating the electronic properties at the metal center. We prepared the new type of ligand MeOTPA and studied the effect of (MeO) on the oxygenation of the complex.