Supramolecular‐Assembly and Surfactant‐Regulated Circularly Polarized Luminescence from a Spiranic BINOL‐Derived Borate Isoindolyl‐Indolenine (BBI) Dye

Abstract Circularly polarized luminescence (CPL) materials have attracted significant attention owing to their unique luminescent properties and their broad range of applications. However, challenges remain, including controlling helical assembly, mitigating aggregation‐caused quenching, and balancing luminescence quantum yield ( Φ PL ) with g values. Here, the study reports the synthesis of a novel asymmetric, spiranic O‐organoboranes bearing isoindolyl‐indolenine scaffold (BBI) with axial chirality through BINOL substitution, as well as its supramolecular assembly and surfactant‐regulated tunable CPL behaviors. The newly designed BBI dye shows relative weak luminescence with a quantum yield of 10% in toluene. Supramolecular assembly in acetonitrile/water co‐solvents exhibit an obvious aggregation‐induced emission (AIE) process, leading to the formation of spherical nanostructures with red‐shifted orange‐yellow CPL (554 nm, g = 0.012, Φ PL = 7%). Moreover, a surfactant sodium dodecyl sulfonate (SDS) can promote the aggregation of BBI in pure deionized water, producing nanofibers with blue‐shifted yellow CPL (536 nm, g = 0.006, Φ PL = 13%). Crystal growth in toluene/hexane and SDS aqueous/acetonitrile systems reveals chiral crystals with the P 212121 space group, offering insights into chirality amplification. This demonstrates the ability to precisely control CPL properties through assembly parameters, with X‐ray single‐crystal analysis providing additional understanding of chirality regulation.