Photophysical Study of New Versatile Multichromophoric Diads and Triads with BODIPY and Polyphenylene Groups

The photophysical properties of multichromophoric dyes with borondipyrromethene (BODIPY) and poly-p-phenylene (di-p-phenylene and tri-p-phenylene) groups in the same molecule are studied in detail. The excitation of the polyphenylene moiety in the UV region leads to a strong visible fluorescent emission of the BODIPY chromophore, via intramolecular excitation energy transfer between both groups. Consequently, these multichromophoric dyes are characterized by a large “virtual” Stokes shift, with a high fluorescence capacity and an efficient laser emission. On the other hand, the photophysical properties of a related dichromophoric dye with a hydroxy end group at the di-p-phenylene moiety show an important decrease in the fluorescent emission due to a photoinduced electron transfer process in basic media. Therefore, its photophysical properties are sensitive to the environmental acidity/basicity and could be applied as a proton sensor.