Merging dynamic and static chirality in propeller-shaped carbazole oligomers via chiral amine substitution

Abstract

Organic emissive materials exhibiting circularly polarized luminescence (CPL) have attracted considerable attention as promising candidates for next-generation photonic and electronic devices. However, most CPL-active molecules require laborious procedures such as asymmetric synthesis or optical resolution. In this study, chiral propeller-shaped molecules were conveniently synthesized by introducing chiral amines possessing static chirality into a dynamically chiral propeller framework. The molecule was obtained via a two-step aromatic nucleophilic substitution (S_NAr) sequence and exhibited distinct CPL activity (|g_lum| ≈ 2.0 × 10⁻³ at room temperature) without optical resolution. Furthermore, a bifunctionalized derivative employing a chiral diamine with a similar substructure was synthesized, but no enhancement in CPL anisotropy was observed. These results indicate that precise control over the relative orientation of the magnetic and electric transition dipole moments is crucial for improving CPL performance.