Synthesis, spectroscopic characterization, one and two-photon absorption properties, and electrochemistry of truxene pi-expanded BODIPYs dyes

A series of mono- and bis-BODIPY substituted truxene derivatives were synthesized by the Knoevenagel condensation reaction and were fully characterized by NMR and HRMS. The photophysical properties of these new dyes have been investigated by UV-vis absorption spectroscopy, steady-state as well as time-resolved fluorescence spectroscopy and two-photon excited spectroscopy. Their electrochemical properties were investigated using cyclic voltammetry. The new dyes exhibit excellent photophysical properties in red to near-infrared region, including large extinction coefficients and high fluorescence quantum yields in methylene chloride solutions. These truxene-BODIPY dyads and triads also exhibit remarkable two-photon absorption cross section sigma(2) up to 6000 GM at 800 nm.