Electrochemical and optical aspects of cobalt meso-carbazole substituted porphyrin complexes

A series of cobalt (II) porphyrin complexes modified with carbazole rings at one or more meso positions of the macrocycle were synthesized and characterized as to their spectroscopic and basic electrochemical properties in non-aqueous media. The effect of the number and position (syn and anti) of carbazole groups on the complexes properties were investigated. The comparison was made to cobalt (II) porphyrin containing mesityl groups at the meso-positions. The relation between the site of redox processes in cobalt meso-carbazole substituted porphyrins were analysed. It was shown that the conjugated π-ring system of the porphyrin macrocycle, the cobalt central metal ion and the carbazole peripheral substituents are redox-active.