Heteroleptic [Bis(oxazoline)](dipyrrinato)zinc(II) Complexes: Bright and Circularly Polarized Luminescence from an Originally Achiral Dipyrrinato Ligand

The world of organic luminophores has been confined for a long time to fairly standard biological labeling applications and to certain analytical tests. Recently, however, the field has undergone a major change of direction, driven by the dual needs to develop novel organic electronic materials and to fuel the rapidly emerging nanotechnologies. Among the many diverse fluorescent molecules, the Bodipy family, first developed as luminescent tags and laser dyes, has become a cornerstone for these new applications. The near future looks extremely bright for "porphyrin's little sister".

Optical probes that provide information about local chirality have been developed based on changes to the circular polarisation of emitted light. Highly emissive complexes of lanthanide ions are ideally suited for CPL spectroscopy and the design criteria for developing such probes are defined, based on a rigorous stereochemical analysis. The perturbation of a dynamically racemic complex may occur either by a change in complex constitution or by non-covalent association. With complexes of enantiopure ligands, perturbation may involve either dynamic helicity inversion or a reversible change in the lanthanide coordination environment.