Novel mono- and di-ferrocenyl bipyridyl ligands: syntheses, electrochemistry, and electropolymerisation studies of their ruthenium(II) complexes

The syntheses and electrochemical properties of new mono- and di-ferrocenyl bipyridyl ligands containing trans conjugated olefinic linkages between the ferrocene redox centres and the 4,4′-substituted 2,2′-bipyridine (bipy) moieties are described. The corresponding ruthenium(II) complexes have been prepared and one complex, [RuL4(bipy)2][PF6]2[L4= 4,4′-bis(ferrocenylvinyl)-2,2′-bipyridine], undergoes electrochemical polymerisation to produce an electrochromic polymer film.