Enhancing Optical Activities of Benzimidazole Derivatives through Coassembly for High-Efficiency Synthesis of Chiroptical Nanomaterials and Accurate ee % Detection of Natural Acids

Developing efficient protocols to enhance the optical activities of chiral self-assemblies is a key to realizing their chiroptical functions such as chiral sensing and displays. Here, we have reported a coassembly protocol to efficiently boost the chiroptical responses, whereby the synthesis of chiroptical nanomaterials and highly accurate detection of enantiomeric excess (ee %) were achieved. A series of benzimidazole derivatives with different topologies underwent spontaneous aggregation and symmetry breaking in solution, generating silent Cotton effects, yet exclusive weak left-handed circularly polarized luminescence (CPL). The coassembly with natural hydroxyl acids via complementary H bonds afforded chiral nanostructures with emerged Cotton effects and enhanced CPL. Dissymmetry g-factors were dramatically boosted (g(lum) from 1 x 10(-3) to 5.5 x 10(-2), g(abs) from 0 to 6.7 x 10(-3)). In addition, proof of concept of recognition and detection of natural chiral molecules was realized with high accuracy.

Automated summary

Efficient protocols were developed to enhance the optical activities of chiral self-assemblies, leading to improved chiroptical responses and accurate detection of enantiomeric excess. Coassembly with natural hydroxyl acids resulted in the formation of chiral nanostructures with enhanced chiral recognition and detection capabilities, showing increased dissymmetry g-factors.