Oxidation of terthiophene substituted with ferrocenyl groups

Terthiophenes substituted with ferrocenyl or methyl groups were prepared by a palladium-catalyzed cross-coupling reaction. The oxidation processes and the oxidized states of the compounds were investigated by cyclic voltammet ry, coulometry, and electronic absorption spectroscopy. The first oxidation of the ferrocenyl-terthiophenes took place on the ferrocene moiety; the re sultant oxidized states spread over the terthiophene moiety. This implies t he charge transfer from the ferricinium ion moiety to the terthiophene moie ty.