Superior Circularly Polarized Luminescence Brightness Achieved with Chiral Heteroleptic Nine-Coordinate Coumarin-Based Tb Complexes.

In order to facilitate the practical application of circularly polarized luminescence (CPL) active molecules, the CPL brightness () must be optimized. We have applied a binary modular strategy to synthesize two chiral organo-Tb complexes, [Tb(Coum)(1,2-Ph-PyBox)] () and [Tb(Coum)(1,2-Ph-PyBox)] (), combining 3-acetyl-4-hydroxy-coumarin () and enantiopure 2,6-bis(4-phenyl-2-oxazolin-2-yl) pyridine (,/,). The photophysical properties of these novel complexes have been fully characterized. The combined point-chiral induction capability of chiral bis(oxazoline) derivatives and the outstanding photophysical properties of the coumarin-derived ligand have resulted in an intense excited-state chiroptical activity (|| = 0.097-0.103) for both Tb enantiomers, with a bright Tb-centered high-purity green emission ( = 74%) and enhanced antenna-centered absorption behavior ( = 47820-47940 M cm). A superior (1132.7-1205.8 M cm at D → F) has been established for complexes and . The strategy adopted in this work provides a new route to chiroptical organo-Tb luminophores with outstanding comprehensive performance.