Structure dependence of intramolecular electron transfer reactions of simple dyads of a zinc(ii) porphyrin complex bearing a peripheral bipyridine moiety.

New dyad systems based on a zinc(ii) porphyrin complex and a 2,2'-bipyridine moiety linked by amide bridges having various bridging groups were synthesized. The photochemical behavior was investigated using fluorescence spectroscopy and a time-resolved absorption technique. The singlet excited state of the porphyrin complex was found to be partially quenched by Cu in methanol, and a photoinduced electron transfer from the excited state of the porphyrin moiety to the Cu(ii)-bipyridine moiety was observed using a transient absorption technique.