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The reactivity of the shortened salen-type ligands H₃salmp, H₂salmen and H₂sal(<i>p</i>-X)ben with variable <i>para</i>-substituent on the central aromatic ring (X = <i>t</i>Bu, Me, H, F, Cl, CF₃, NO₂) towards the trivalent metal ions manganese(III) and iron(III) is presented. The selective formation of the dinuclear complexes [M₂(μ-salmp)₂], M = Mn (<b>1a</b>), Fe (<b>2a</b>), [M₂(μ-salmen)₂(μ-OR)₂)], R = Et, Me, H and M = Mn (<b>3a</b>–<b>c</b>) or Fe (<b>4a</b>–<b>c</b>), and (M₂(μ-sal[<i>p</i>-X]ben)₂(μ-OMe)₂), X = <i>t</i>Bu, Me, H, F, Cl, CF₃, NO₂ and M = Mn (<b>5a</b>–<b>g</b>) or Fe (<b>6a</b>–<b>g</b>), could be identified by reaction of the Schiff bases with metal salts and the base NEt₃, and their characterization through elemental analysis, infrared spectroscopy, mass spectrometry and single-crystal X-ray diffraction of <b>2a</b>·2AcOEt, <b>2a</b>·2CH₃CN and <b>3c</b>·2DMF was performed. In the case of iron(III) and H₃salmp, when using NaOH as a base instead of NEt₃, the dinuclear complexes [Fe₂(μ-salmp)(μ-OR)(salim)₂], R = Me, H (<b>2b</b>,<b>c</b>) could be isolated and spectroscopically characterized, including the crystal structure of <b>2b</b>·1.5H₂O, which showed that rupture of one salmp³⁻ to two coordinated salim⁻ ligands and release of one salH molecule occurred. The same hydrolytic tendency could be identified with sal(<i>p</i>-X)ben ligands in the case of iron(III) also by using NEt₃ or upon standing in solution, while manganese(III) did not promote such a C–N bond breakage. Cyclic voltammetry studies were performed for <b>3b</b>, <b>4b</b>, <b>5a</b> and <b>6a</b>, revealing that the iron(III) complexes can be irreversibly reduced to the mixed-valence Fe^IIFe^III and Fe^II₂ dinuclear species, while the manganese(III) derivatives can be reversibly oxidized to either the mixed-valence Mn^IIIMn^IV or to the Mn^IV₂ dinuclear species. The super-exchange interaction between the metal centers, mediated by the bridging ligands, resulted in being antiferromagnetic (AFM) for the selected dinuclear compounds <b>3b</b>, <b>4b</b>, <b>5a</b>, <b>5e,</b><b>5f</b>, <b>6a</b> and <b>6e</b>. The coupling constants <i>J</i> (–2<i>J</i><b>Ŝ</b>₁<b>·</b><b>Ŝ</b>₂ formalism) had values around −13 cm⁻¹ for manganese(III) compounds, among the largest AFM coupling constants reported so far for dinuclear Mn^III₂ derivatives, while values between −3 and −10 cm⁻¹ were obtained for iron(III) compounds.