Synthesis and Properties of BODIPY Appended Tetraphenylethylene Scaffolds as Photoactive Arrays

Abstract

Tetraphenylethylene (TPE) and its derivatives exhibit excellent aggregation-induced emission (AIE) properties. The TPE unit is easily accessible and many functional groups can be introduced in a facile manner to yield effective luminescent materials in both solution and the solid-state. It is because of this, several TPE-based compounds have been developed and applied in many areas, such as OLEDs and chemical sensors. Boron dipyrromethanes (BODIPYs) are a class of pyrrolic fluorophore of interest with myriad application in both material science and biomedicine. Through the combination of Pd-catalyzed cross-coupling reactions and traditional dipyrromethane chemistry, we present the syntheses of novel tetra-BODIPY-appended TPE derivatives with different ‘arm’ lengths. The TPE-BODIPY arrays 6 and 9 show vastly differing AIE properties in THF/H 2 O systems, with 9 exhibiting dual-AIE, along with both conjugates being found to produce singlet oxygen ( 1 O 2 ). We presume the synthesized BODIPY-appended TPE scaffolds to be utilized for potential applications in the fields of light harvesting systems and delivery of photosensitizers and for the construction of porous materials.