Syntheses and molecular structures of cis and trans monomeric ferrocenecarboxylatocopper(l1) complexes with imidazole derivatives

Article in Journal of Chemical SocietyThe products of the reactions of 1,2-dimethyIimidazole and N-methylimidazole with tetrakis(ferr0-cenecarboxylato)dicopper( 11) have been isolated and characterized by single-crystal X-ray diffraction. They are the monomeric species cis- bis( 1,2-dimethylirnidazole) bis(ferrocenecarboxylato)copper( 11) 1 and trans- bis (ferrocenecarboxylato) bis(N- methylimidazo1e)copper ( I I) 2, respectively. In each complex the copper ion is in a square-planar environment consisting of two imidazole nitrogen atoms and a carboxylate oxygen atom from each ferrocenecarboxylate ligand. The second oxygen atoms of the carboxylate functionalities are involved in weak interactions with the copper ions. The q5-C5H, and q5-C5H5 rings of the ferrocenyl moieties are nearly eclipsed with deviations from the eclipsed conformation of 9.7 and 5.5" for 1 and 4.4" for 2