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.