Fe-III complexes of the symmetric (2S,2'S)-[N,N'-bis(1-(2-hydroxy-3,5-di-tert-butylphenylmethyl))1-2,2'- bipyrrolidine (H2L1) and dissymmetric (2S,2'S)-[N,N'-(1-(2-hydroxy-3,5-di-tert-butylphenylmethyl))-2-(pyridylmethyl)]- 2,2'-bipyrrolidine (HL2) ligands incorporating the bipyrrolidine backbone were prepared, and the electronic structure of the neutral and one-electron oxidized species was investigated. Cyclic voltammograms (CV) of (FeLCl)-Cl-1 and (FeLCl2)-Cl-2 showed expected redox waves corresponding to the oxidation of phenoxide moieties to phenoxyl radicals, which was achieved by treating the complexes with 1 equiv of a suitable chemical oxidant. The clean conversion of the neutral complexes to their oxidized forms was monitored by UV-vis-NIR spectroscopy, where an intense pi-pi* transition characteristic of a phenoxyl radical emerged [(FeLCl)-Cl-1](+center dot): 25 500 cm(-1) (9000 M-1 cm(-1)); [(FeLCl2)-Cl-2](+center dot): 24 100 cm-1 (8300 M-1 cm(-1)). The resonance Raman (rR) spectra of [(FeLCl)-Cl-1](+center dot) and [(FeLCl2)-Cl-2](+center dot) displayed the characteristic phenoxyl radical nu(7a) band at 1501 and 1504 cm(-1), respectively, confirming ligand-based oxidation. Electron paramagnetic resonance (EPR) spectroscopy exhibited a typical high spin Fe-III (S = 5/2) signal for the neutral complexes in perpendicular mode. Upon oxidation, a signal at g 9 was observed in parallel mode, suggesting the formation of a spin integer system arising from magnetic interactions between the high spin Fe-III center and the phenoxyl radical. Density functional theory (DFT) calculations further supports this formulation, where weak antiferromagnetic coupling was predicted for both [(FeLCl)-Cl-1](+center dot) and [(FeLCl2)-Cl-2](+center dot).