Spectroelectrochemical studies of cobalt(II) porphyrins with paracyclophanyl, pyridinium and nucleoside substituents

Abstract

This work describes the synthesis of novel cobalt complexes of porphyrins: ( meso-tetrakis [2.2]paracyclophanylporphyrinato)cobalt(II) (T(PCP)PCo(II)); ( meso-mono[2.2]paracyclophanyltriphenylporphyrinato)cobalt(II) (PCPPCo(II)); ( meso-tetrakis(5′-0- p-phenylene-2′,3′-0-isopropylideneuridine)porphyrinato)cobalt(II) (TPUPCo(II)), and ( meso-5′-0- p-phenylene-2′,3′-0-isopropylideneuridinetri( N-methyl-4-pyridinium)porphyrinato)cobalt(II) (PUPCo(II)). The redox properties of these complexes were characterized by voltammetry and UV—visible spectroelectrochemistry. The effects of the electron-donating and electron-withdrawing properties of the substituents on the electrochemical and spectroscopic data obtained are described and discussed. These compounds are the first examples of a linkage of a biomolecule, such as uridine, with the porphyrin system. These porphyrins also undergo electrochemical polymerization with the formation of conductive films.