Circularly Polarized Luminescence from Helically Chiral N, N, O, O‐Boron‐Chelated Dipyrromethenes

Abstract

Helically chiral N, N, O, O‐boron chelated dipyrromethenes showed solution‐phase circularly polarized luminescence (CPL) in the red region of the visible spectrum ( λ _em(max) from 621 to 663 nm). The parent dipyrromethene is desymmetrised through O chelation of boron by the 3,5‐ ortho‐phenolic substituents, inducing a helical chirality in the fluorophore. The combination of high luminescence dissymmetry factors (| g _lum| up to 4.7 ×10 ⁻³) and fluorescence quantum yields ( Φ _F up to 0.73) gave exceptionally efficient circularly polarized red emission from these simple small organic fluorophores, enabling future application in CPL‐based bioimaging.