Synthesis and spectral properties of phthalocyanine–BODIPY conjugates

Various zinc phthalocyanines were substituted at ortho or meta positions with 1,3,5,7-tetramethyl-8-phenyl-4,4-difluoroboradiazaindacene (BODIPY) moieties via Pd catalyzed Sonogashira-coupling reactions, at either meso or β positions of the BODIPY. UV–Vis and fluorescence emission spectra of the conjugates exhibit panchromatic behavior due to their absorption over a broad spectral region from ultraviolet to visible and energy transfer from the excited BODIPY substituent to the phthalocyanine core. Some conjugates show red-shifted Q-bands that correlate to the planarity and dihedral angle between the subunits, as well as the position and number of attached BODIPY and phthalocyanine moieties.