Spiro-BODIPYs with a Diaryl Chelate: Impact on Aggregation and Luminescence

Spiro-BODIPYs with a diaryl chelate unit have been found to form J-aggregates in methanol–water solvent mixture and brightly emissive in the solid state. The diaryl chelate unit has a significant impact on J-aggregates and fluorescence of BODIPYs. Crystal structural analysis reveals that the spiro-structures facilitate J-stacking in the solid state.