Modular approach toward supramolecular functional assemblies: Remote control of fluorescence

A supramolecular Zn-porphyrin-free-base porphyrin dyad, in which efficient energy transfer occurs, was constructed. The energy-transfer process can be switched on and off by replacing C an axial ligand on the Zn-porphyrin, making it possible to remotely control fluorescence from the free-base porphyrin. An implication to logic gates is discussed.