Circularly polarized luminescence of encaged Eu(iii) and Tb(iii) complexes controlled by an inherently chiral remote unit

A molecular cage-based approach to obtain enantiopure lanthanide complexes with circular polarized luminescence (CPL) activities is presented. Hemicryptophane endohedral complexes were designed by functionalizing the molecular cage with pyridine-2,6-dipicolinamide coordinating groups. Taking advantage of the ability of the inherent chirality of the remote cyclotriveratrylene (CTV) unit to propagate along the linkers of the molecular cage, the encapsulated lanthanide complexes with a controlled chirality have been obtained. In this way, we obtained the CPL active Tb(iii) and Eu(iii) cages although the chiral CTV unit is located far from the complexation sites. This opens the way for a broader use of enantiopure covalent cages for CPL applications.