Control of Circularly Polarized Luminescence through Hydrogen-Bond-Assisted Atropisomer Resolution in a Dinuclear Boron Difluoride Complex

Controlling the sign and magnitude of circularly polarized luminescence (CPL) through conformational chirality remains a challenging yet attractive strategy for the development of chiral photofunctional materials. In this study, hydrogen-bond-assisted control of CPL is reported in a dinuclear boron difluoride complex cocrystallized with organic salts. Two atropisomers, (SC,SC,Ra,Ra) and (SC,SC,Sa,Sa), are separately obtained under different recrystallization conditions. Importantly, each crystalline form exhibits opposite CPL handedness and distinct luminescence efficiencies. These findings provide novel design principles for the development of conformationally flexible CPL emitters.