Achieving Chiral Recognition of Imide-Based Fluorophores Through Förster Resonance Energy Transfer: Special Collection: 2025 Emerging Investigators

Precise enantiomer discrimination is crucial across diverse fields; however, developing a rapid and solvent-free strategy for chiral discrimination is still difficult to achieve. Here, we present a chirality-dependent Förster resonance energy transfer (FRET) system for enantiomer discrimination in the solid state. Perylene diimide (PDI) enantiomers serve as fluorescent selectands (guests), while chiral naphthalimide (NMI) or naphthalene diimide (NDI) act as chiral selectors (hosts). Photophysical studies reveal that host and guest with homochirality exhibit markedly enhanced fluorescence compared to heterochiral counterparts, attributed to more efficient FRET. In contrast, control experiments under FRET-suppressed conditions fail to effectively discern molecular chirality. Molecular dynamics simulations reveal that homochiral host and guest tend to adopt more compact molecular packing, thereby promoting FRET. This work provides a noncovalent fluorescence-based platform for real-time enantioselective recognition in the solid state.