Chiral Induction and Memory via Supramolecular Deracemization

Abstract

Chirality is intrinsic to nature, and control of molecular chirality remains at the forefront of the chemical sciences. The introduction of fundamentally new principles to break symmetry, leading to the formation of a specific enantiomer, is particularly challenging with important implications in numerous scientific fields. Herein we present a helically chiral dynamic molecular switch whose enantiomers are connected via a single symmetric metastable state that can be populated via light or redox stimuli. Relaxation of the prochiral state in the presence of a bound chiral ammonium guest results in the preferential formation of a specific enantiomer through a conceptually unique supramolecular deracemization process. Importantly, the formed host enantiomer is stable even in the absence of guest, enabling reversible and stable chiral information transfer, while oxidation of the host results in an enantioenriched dication that is insensitive to light, allowing orthogonal chiral memory.