Chemical and electrochemical generation of [Fe(bpy)2(S)2]2+ (bpy = 2,2′-bipyridine, S = H2O or CH3CN).: A route for synthesis of coordinatively dissymmetrical iron(II) polypyridine complexes and supramolecular structures containing a Fe(bpy)32+ moiety

A route for the synthesis of coordinatively dissymmetrical iron(II) polypyridine complexes [Fe(L)(2)L'](2+) (L and L' are two different 2,2'-bipyridine derivatives) is described. The procedure is based on the use of the precursor [Fe(L)(2)(CH3CN)(2)](2+) (L = 2,2'-bipyridine), which can be easily prepared by electrochemical or chemical reduction of the mu-oxo diaqua diiron(III) complex [Fe2O(bpy)(4)(H2O)(2)](4+) in acidic CH3CN solution. In addition, it is shown that this procedure can be applied with success to the synthesis of covalently linked heterodinuclear complexes containing, for instance, Fe(bpy)(3)(2+) and Ru(bpy)(3)(2+) moieties. The electrochemical behaviour of all these new complexes is reported.