Porphyrin–Bodipy combination: synthesis, characterization and antenna effect

Abstract

This paper described the synthesis of multichromophoric and π-conjugated macromolecules consisting of two equal Bodipy units and one porphyrin unit (free base). Then, a zinc(II) complex of this macromolecule based on Bodipy and porphyrin was prepared by a classical complex reaction. The formation of nitroporphyrin, aminoporphyrin, Bodipy–porphyrin (PB) and Bodipy–metalloporphyrin (Zn–PB) was confirmed by ¹H-NMR, ¹³C-NMR, elemental analysis, UV-vis/fluorescence spectra, melting point and ESI-TOF-MS techniques. Moreover, the photophysical properties of chromophoric groups such as absorption, emission and quantum yields were investigated for the photoinduced energy transfer in three different organic solvents. The result indicated that the emission of Bodipy in the Bodipy–porphyrin combination was significantly quenched with the formation of the free base and zinc(II) complex of porphyrin. Efficient energy transfer from the Bodipy unit to the porphyrins (free base or Zn–chelate) was observed between 88% and 96% due to high π-conjugation. The energy transfer also occurred from Bodipy to porphyrin though the high polarity of acetonitrile.