Circularly Polarised Luminescence from Helically Chiral “Confused” N,N,O,C‐Boron‐Chelated Dipyrromethenes (BODIPYs)

Chiral organic fluorophores have significant promise in the development of efficient emitters of circularly polarized light. Herein we describe a helically chiral boron dipyrromethene (BODIPY) with a hitherto unreported N , N , O , C ‐boron‐chelation motif, synthesised by means of a one‐pot boron metathesis, nucleophilic aromatic substitution (S N Ar), Suzuki coupling, boron chelation, cascade reaction. Resolution of the racemic BODIPY (by preparative HPLC on a chiral stationary phase) allowed examination of the chiroptical properties of the resulting enantiomers ( λ max (abs)=593 nm, λ max (em)=622 nm, ϵ =30 000 m −1 cm −1 , φ F =0.49, |g lum |=3.7×10 −3 (hexane)). This is the first example of circularly polarised emission from a non‐ C 2 ‐symmetric helically chiral N , N , O , C ‐BODIPY and as such provides a valuable benchmark for future developments in this compound series.