Palladium Catalyzed, Annulative Multiple C-H Bond Activations of BODIPYs to Access π-Extended Polycyclic Heteroaromatic Molecules with Deep Red Emissions and self-aggregation Behaviors.

Abstract

Aromatic ring fusion on BODIPY core can effectively tune its electronic property, and red-shift the absorption and emission wavelength. In this work, we report that a one-pot Pd(II) catalyzed multiple C-H activation to access acenaphtho[b]-fused BODIPYs though the reaction of α,β-unsubstituted-BODIPYs and 1,8-dibromonaphthalenes. These newly synthesized acenaphtho[b]-fused BODIPYs revealed intensified deep red absorptions (639 - 669 nm) and emissions (643 - 683 nm), with high fluorescence quantum yields (0.53 - 0.84) in dichloromethane. Notably, these acenaphtho[b]-fused BODIPYs exhibited well-defined self-aggregation behavior in water/THF mixture, and for instance, the absorption of 3a was red-shifted by 53 to 693 nm after formingaggregates.