Biased Symmetry Breaking and Chiral Control by Self-Replicating in Achiral Tetradentate Platinum (II) Complexes

Angew Chem Int Ed Engl. 2021 May 3;60(19):10531-10536. doi: 10.1002/anie.202101709. Epub 2021 Apr 6.

Abstract

Obtaining homochirality from biased symmetry-breaking of self-assembly in achiral molecules remains a great challenge due to the lack of ingenious strategies and controlling their handedness. Here, we report the first case of biased symmetry breaking from achiral platinum (II) liquid crystals which self-organize into an enantiomerically enriched single domain without selection of handedness in twist grain boundary TGB [ *] phase. Most importantly, the chiral control of self-organization can be achieved by using above the homochiral liquid crystal films with determined handedness (P or M) as a template. Moreover, benefiting from self-assembled superhelix, these complexes exhibit prominent circularly polarized luminescence with high |glum | up to 3.4×10-3 in the TGB [ *] mesophase. This work paves a neoteric avenue for the development of chiral self-assemblies from achiral molecules.

Keywords: chiral amplification; circularly polarized luminescence; phosphorescence; platinum(II) liquid crystals; symmetry breaking.