Highlights on the Road towards Highly Emitting Solid-State Luminophores: Two Classes of Thiazole-Based Organoboron Fluorophores with the AIEE/AIE Effect

Developing a novel, small-sized molecular building block that may be capable of emitting light in the solid state is a challenging task and has rarely been reported in the literature. BF₂ -containing dyes seem to be promising candidates towards this aim. Two series of new N^NBF₂ complexes showing aggregation-induced emission (AIE) and aggregation-induced emission enhancement (AIEE) were designed and synthesized by means of a new protocol, which improved on the traditional method by employing microwave irradiation. The optical and photophysical properties of the BF₂ complexes were investigated in depth. The synthesized complexes showed fluorescence in both solution and the solid state and, in a mixture of tetrahydrofuran/water, may aggregate into fluorescent nanoparticles. The experimental investigation was supported by quantum mechanical calculations. Their availability, stability, large Stokes shifts, and aggregation capabilities, along with their solid-state emission capability, render this new class of BF₂ complexes promising AIEE/AIE fluorophores for further applications in the fields of fluorescence imaging and materials science.