Porphyrin-Azobenzene-Bodipy Triads: Syntheses, Structures, and Photophysical Properties.

Cyclic and acyclic azobenzene bridged porphyrin-dipyrrin derivatives were successfully prepared via Suzuki-Miyaura coupling reaction of α,α'-diborylated dipyrromethane with bromoazophenyl porphyrin or reaction of borylated porphyrin with dibromoazophenyl dipyrrin, and the corresponding porphyrin-Bodipy derivatives were obtained by subsequent boron complexation. The cyclic porphyrin-dipyrrin compound 3Ni was confirmed by X-ray diffraction. The low fluorescence quantum yields of azobenzene bridged porphyrin-Bodipy can be ascribed to the presence of the intramolecular charge transfer state.