"Redox Chemistry of FeII and FeIII complexes using carboxylatebased ligands"

Two new complexes [FeII(L1OO)(H2O)2][ClO4]·2H2O (1), and [FeIII(L1OO)Cl3] (2), (L1OO– = 3-[(2-(pyridine-2-yl)-ethyl){2-(pyridine-2-yl)methyl}amino]propionate) have been synthesized and characterized by elemental analysis, IR, and UV/Vis spectroscopy. In 1 distorted octahedral FeN3O3 coordination is satisfied by three nitrogen atoms and an appended carboxylate oxygen atom of the ligand, and the oxygen atoms from water molecule. In 2 distorted octahedral FeN3Cl3 coordination is satisfied by three nitrogen atoms and three chlorine atoms. When examined by cyclic voltammetry (CV), complex 1 undergoes in DMF one quasi-reversible metal-based (FeII/FeIII) oxidation [E1/2 = 0.325 V vs SCE (saturated calomel electrode)]; whereas complex2 undergoes in CH3CN one quasi-reversible metal-based (FeIII/FeII) reduction [E1/2 = ‒0.055 V vs SCE (saturated calomel electrode)].