Synthesis and Properties of Bright Red-to-NIR BODIPY Dyes for Targeting Fluorescence Imaging and Near-Infrared Photothermal Conversion

Abstract

An efficient synthesis of 3-pyrrolylBODIPY dyes has been developed from a rational mixture of various aromatic aldehydes and pyrrole in a straightforward condensation reaction, followed by in situ successively oxidative nucleophilic substitution using a one-pot strategy. These resultant 3-pyrrolylBODIPYs without blocking substituents not only exhibit the finely tunable photophysical properties induced by the flexible meso-aryl substituents but also serve as a valuable synthetic framework for further selective functionalization. As a proof of such potential, one 3-pyrrolylBODIPY dye (581/603 nm) through the installation of the morpholine group is applicable for lysosome-targeting imaging. Furthermore, an ethene-bridged 3,3′-dipyrrolylBODIPY dimer was constructed, which displayed a near-infrared (NIR) emission extended to 1200 nm with a large fluorescence brightness (2840 M–1 cm–1). The corresponding dimer nanoparticles (NPs) afforded a high photothermal conversion efficiency (PCE) value of 72.5%, eventually resulting in favorable photocytotoxicity (IC50 = 9.4 μM) and efficient in vitro eradication of HeLa cells under 808 nm laser irradiation, highlighting their potential application for photothermal therapy in the NIR window.

Synthesis and properties of covalently linked phenyl bridged 3-pyrrolyl BODIPY–BODIPY dyads

“…13 However, the synthesis of the BF 2 complex of α-pyrrolyl dipyrrin has not been thoroughly explored in previous studies due to the inaccessibility of α-pyrrolyl dipyrrin ligands. Recently, we 14–21 and others 22–25 developed a simple and facile synthetic route for BF 2 complexes of meso -aryl α -pyrrolyl dipyrrins 3a (Fig. 1).…”