Zusammenfassung
In a one-pot reaction of N(5-methylthiazole-2-yl)-thiazole-2-carb- oxamide HL2 (3) with iron(ii) acetate in air, the homotrinuclear heteroleptic mixed-valent oxo-centered iron cluster [(FeFe2O)-Fe-II-O-III(L-2)(3)(OAc)(3)] (4) was formed. Exchange of iron(ii) in 4 by nickel(ii) afforded the heteronuclear cluster [(NiFe2O)-Fe-II-O-III(L-2)(3)(OAc)(3)] (6). crystals suitable for X-ray structure ...
Zusammenfassung
In a one-pot reaction of N(5-methylthiazole-2-yl)-thiazole-2-carb- oxamide HL2 (3) with iron(ii) acetate in air, the homotrinuclear heteroleptic mixed-valent oxo-centered iron cluster [(FeFe2O)-Fe-II-O-III(L-2)(3)(OAc)(3)] (4) was formed. Exchange of iron(ii) in 4 by nickel(ii) afforded the heteronuclear cluster [(NiFe2O)-Fe-II-O-III(L-2)(3)(OAc)(3)] (6). crystals suitable for X-ray structure analyses, in 4 and 6, the OAc- co-ligands were exchanged by OBz(-) ligands to give [(FeFe2O)-Fe-II-O-III(L-2)(3)(OBz)(3)] (5) and [(NiFe2O)-Fe-II-O-III(L-2)(3)(OBz)(3)] (7). The complexes 5 and 7 are isostructural and made up of three ditopic, tridentate ligands (L-2)(-) and three bridging ben-zoate co-ligands, which fix the three metal ions in the corners of a triangle with an mu(3)-O2- ion in the center. The mixed-valent character of 4-7, their intramolecular electron-exchange processes, and their redox properties were studied by variable-temperature Mossbauer spectroscopy and cyclic voltammetry.