Homochiral self-sorting of BINOL macrocycles

Chiral arylene-ethynylene macrocycles (AEMs) were synthesized via alkyne metathesis-mediated depolymerization of BINOL-based polymers. Homochiral dimers are selectively obtained from metathesis of heterochiral polymers. Thermodynamic analysis and computational modeling suggests the homochiral self-sorting to be entropy-driven due to the greater symmetry of the homochiral dimers over the heterochiral dimer. This symmetry-controlled reaction is a novel approach to achieving high selectivity in dynamic covalent macrocycle synthesis. Importantly, the result describes a new paradigm in dynamic covalent chemistry that will enable efficient synthesis of new chiral architectures.