Aggregation‐Dependent Circularly Polarized Luminescence and Thermally Activated Delayed Fluorescence from Chiral Carbene‐Cu<sup>I</sup>‐Amide Enantiomers
Ying Ao, Yuhan Ai, Chuluo Yang, Shaolong Gong
Abstract
Abstract The field of luminescent carbene‐metal‐amide (CMA) complexes and chiroptical‐active materials has been blossoming in recent years, although chiroptical‐active CMA complexes have not been reported so far. For the first time, a pair of chiral Cu I ‐based CMA enantiomers, ( R,R ) ‐ PSIPr*‐Cu‐DMAC and ( S,S )‐PSIPr*‐Cu‐DMAC , have been developed by using chiral phenyl‐substituted N ‐heterocyclic carbenes as acceptor ligands in the CMA motif. The Cu I ‐based CMA enantiomers exhibited aggregation‐induced circularly polarized luminescence with a large luminescence dissymmetry factor of up to +0.027, the first reported for CMA complexes. This success originates from the limited ligand‐ligand rotation freedom and asymmetrical packing pattern (helical structure) of the CMA enantiomers in the crystals. Moreover, these Cu I enantiomers displayed inspiring aggregation‐dependent thermally activated delayed fluorescence properties. These findings bring new insights into the optical properties of chiral CMA complexes from the perspective of aggregation states.