Design and Structure−Activity Relationship Investigation of Organic Circularly Polarized Luminescent Materials via a Supramolecular Cocrystal Strategy

Abstract A hydrogen bond−directed cocrystallization strategy was employed to resolve the racemic luminescent compound 1-acetyl-3-phenyl-5-(9-anthryl)pyrazoline (APAP) using enantiopure (R)-/(S)-binaphthol as cocrystal formers (CCFs). This approach enabled the successful isolation of homochiral cocrystals(R)-APAP·(R)-binaphthol and (S)-APAP·(S)-binaphtholeach exhibiting distinct circularly polarized luminescence (CPL). Single-crystal X-ray diffraction and 1H NMR spectroscopic analyses confirm a strict 1:1 stoichiometry between APAP and binaphthol in both cocrystals, along with near-identical lattice parameters and overall crystal packing motifs. Crucially, due to the exclusive incorporation of enantiomerically pure APAP and binaphthol components, the two cocrystals constitute a pair of perfect structural enantiomers, as evidenced by mirror-symmetric circular dichroism (CD) and CPL spectra. Moreover, the incorporation of binaphthol molecules disrupted the intrinsic π−π stacking interactions between anthracene chromophores in single-component APAP crystals. As a direct result of this structural reorganization, the solid-state photoluminescence quantum yield (ΦF) is enhanced 5-fold relative to that of pristine racemic APAP crystals.