Photoinduced electron transfer in porphyrin‐quinone cyclophanes, 5. Quinone‐porphyrin‐quinone and quinone‐porphyrin‐donor cyclophanes: Syntheses, structures and electron‐transfer‐related properties

To study the structure dependence of photoinduced electron transfer between porphyrins and quinones the concept of a new family of porphyrin‐quinone cyclophanes with vertical arrangements of porphyrin and quinone units is presented. The syntheses of the quinone‐porphyrin‐quinone cyclophane 1 , the prototype of this series, and of the quinone‐porphyrindonor cyclophanes 12 and 14 are described. Spectroscopic data are discussed with regard to the structures involved and in relation to electron‐transfer reactions occurring in these systems.