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

Abstract

A route for the synthesis of coordinatively dissymmetrical iron(II) polypyridine complexes [Fe(L)₂L′]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 μ-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)₃²⁺ and Ru(bpy)₃²⁺ moieties. The electrochemical behaviour of all these new complexes is reported.