Reactions with o-vanillin produced a novel iron(III) dimer complex, [Fe₂L₂] or Fe₂O₁₂N₄C₄₀H₄₆, from ferric chloride and 2-hydroxy-1,3-diaminopropane. The ferric ions are linked by oxygen bridges via the phenolic oxygens of the o-vanillin. Unlike other complexes with other transition metals, the ferric complex is coordinatively saturated and therefore not well suited for catalytic reactions. The metal atoms couple antiferromagnetically via the briding oxygens.