Boosting Circularly Polarized Luminescence from Alkyl‐Locked Axial Chirality Scaffold by Restriction of Molecular Motions

Abstract

AbstractBoosting the circularly polarized luminescence of small organic molecules has been a stubborn challenge because of weak structure rigidity and dynamic molecular motions. To investigate and eliminate these factors, here, we carried out the structure‐property relationship studies on a newly‐developed axial chiral scaffold of bidibenzo[b,d]furan. The molecular rigidity was finely tuned by gradually reducing the alkyl‐chain length. The environmental factors were considered in solution, crystal, and polymer matrix at different temperatures. As a result, a significant amplification of the dissymmetry factor glum from 10−4 to 10−1 was achieved, corresponding to the situation from (R)‐4C in solution to (R)‐1C in polymer film at room temperature. A synergistic strategy of increasing the intramolecular rigidity and enhancing the intermolecular interaction to restrict the molecular motions was thus proposed to improve circularly polarized luminescence. The though‐out demonstrated relationship will be of great importance for the development of high‐performance small organic chiroptical systems in the future.