A topologically new ruthenium porphyrin-fullerene donor acceptor ensemble

A novel ruthenium porphyrin complex bearing an axially coordinated fullerene ligand (RuP-C60), that is, a fulleropyrrolidine that bears a pyridine moiety, was developed as an artificial reaction center mimic. Generally, the new donor acceptor dyad gives rise to rapid intramolecular deactivation of the ruthenium porphyrin triplet excited state, which evolves from instantaneous intersystem crossing. The product of the ruthenium porphyrin excited-state deactivation depends on the solvent polarity. While in non-polar solvents a transduction of triplet excited energy predominates, in medium and strongly polar media, charge-separation leads to the formation of RuP*+ C60*-.