Thieno[3,2-]thiophene-based bridged BODIPY dimers: synthesis, electrochemistry, and one- and two-photon photophysical properties.

Four BODIPY dyes (6a-6d) with electron-donating or electron-withdrawing groups at the -position were synthesized by the Sonogashira coupling reaction of 2,5-diethynylthieno[3,2-]thiophene with mono-iodo-BODIPY moieties. All compounds were fully characterized by H NMR and MALDI-TOF MS. Their photophysical and electrochemical properties were studied by UV-visible absorption spectroscopy, steady-state and time-resolved fluorescence spectroscopy, two-photon excitation spectroscopy and cyclic voltammetry.