Benzoheterocyclic [ b ]-fused BODIPYs: synthesis and effects of N, O, and S on structure, photophysical properties, and aggregation

A one-pot S N Ar/C–H activation gave six heteroatom-[ b ]-fused BODIPYs, clarifying N, O, and S effects on optoelectronic behavior. The dyes show high Φ F , low K nr , and J -aggregation, and follow a new “half-sum rule” for HOMO/LUMO prediction.