Synthesis and structures of μ3-oxo-centered mixed-valent trinuclear iron complexes with 1-methyl-imidazole ligands

Treatment of the μ3-oxo-centered mixed-valent trinuclear iron complex [Fe3(μ3-O)(μ-OAc)6(H 2O)3] (1) in methanol solution with one, two, or three equivalents of 1-methyl-imidazole (C4H6N2) afforded the substitution products [Fe3(μ3-O)(μ-OAc) 6(H2O)2(C4H6N 2)] (2), [Fe3(μ3-O)(μ-OAc) 6(H2O)(C4H6N2) 2] (3), and [Fe3(μ3-O)(μ-OAc) 6(C4H6N2)3] (4), respectively. Complexes 2-4 were characterized by spectroscopic and elemental analyses, and the crystal structures of complexes 3 · 1.5MeOH · 2H2O and 4 have been determined by single-crystal X-ray diffraction. The results indicate that in 2-4 the trinuclear core unit [Fe 3(μ3-O)(μ-OAc)6] of 1 is preserved. © 2007 Verlag der Zeitschrift für Naturforschung.