The photophysical properties of porphyrinic phenoxynaphthacenequinones 1 and 2 were investigated to assess their potential use as gated photoinduced electron transfer systems. Although the photophysical properties of the porphyrin chromophores remain unaltered upon derivatization, the photochemical isomerization of the naphthacenequinone fragment is shut down due to its intimacy with the porphyrin.