Simultaneous Chiral Fixation and Chiral Regulation Endowed by Dynamic Covalent Bonds.

Abstract

The construction of chiral superstructures through self-assembly of non-chiral polymers usually relies on theinterplay of multiple non-covalent bonds, which is significantly limited by the memory ability of induced chirality. Although the introduction of covalent crosslinking can undoubtedly enhance the stability of chiral superstructures, the concurrent strong constraining effect hinders the application of chirality-smart materials. To address this issue, we have made the first attempt at the reversible fixation of supramolecular chirality by introducing dynamic covalent crosslinking into the chiral self-assembly of side-chain polymers.After chiral induction, the reversible [2 + 2] cycloaddition reaction of cinnamate group in polymer chains can be further controlled by light to manipulate inter-chain crosslinking and decrosslinking.Based on thisphoto-programmable and dynamic chiral fixation strategy,a novel pattern-embedded storage mechanism ofchiral polymeric materials was established for the first time.