Novel BODIPY-bridged cyclotriphosphazenes

Three new 2-component unsubstituted (4P), diiodo- (5P), and dibromo- (6P) distyryl-BODIPY-bridged cyclotriphosphazene dimers were designed and synthesized. The newly synthesized BODIPY-cyclotriphosphazene systems were characterized by 1 H, 13 C, and 31P NMR spectroscopy. The photophysical properties of the distryl-BODIPYs (4–6) and BODIPY-cyclotriphosphazene dyads (4P–6P) were studied by UV-Vis absorption and fluorescence emission spectroscopy. In these derivatives, the bino-type cyclotriphosphazene derivative bearing unsubstituted BODIPY unit 4 P exhibited high fluorescence and no singlet oxygen generation due to the lack of spin converter. The attachment of heavy atoms (iodine and bromine) enabled the production of singlet oxygen.