Chirality Transfer in Coassembled Organogels Enabling Wide-Range Naked-Eye Enantiodifferentiation

ACS Nano. 2019 Nov 26;13(11):12438-12444. doi: 10.1021/acsnano.9b06250. Epub 2019 Oct 1.

Abstract

Enantiodifferentiation is crucial in organic chemistry, pharmacochemistry, material chemistry, and life science. However, it remains tremendously challenging to achieve a broad enantioselectivity to different types of chiral substrates via a single-material design. Here, we report a coassembled organogel strategy with chirality transfer to make an enantioselective generality possible. This coassembly contains two components: a chiral rigid molecular linker and an achiral block copolymer. Different from routine helically packed chiral self-assemblies, chirality transfer from the linker to the copolymer directed the coassembly to form a phase-segregated twisted nanofiber, in cooperation with H-bonding and microphase segregation. An organogel was accordingly formed by the further cross-linking in ethanol, where the rigid chiral linker served as the scaffold. On this basis, the system becomes highly sensitive, enabling a naked-eye sensing toward the single enantiomer of a diverse series of chiral species (including axial, point, planar, and polymeric chirality) via gel-to-micelle transformation, due to the asymmetric interaction hampering the chirality transfer in the coassembly and destroying the hierarchical structure. Such a strategy, based on a significant amplification of the stereoselective interactions, facilitates a simple and straightforward way to distinguish a broad optical activity independent of devices.

Keywords: block copolymers; chirality; coassembly; enantioselectivity; organogel.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gels* / chemistry
  • Gels* / metabolism
  • Humans
  • Hydrogen Bonding
  • Materials Testing
  • Molecular Structure
  • Nanofibers* / chemistry
  • Nanofibers* / ultrastructure
  • Polymers* / chemistry
  • Polymers* / metabolism
  • Stereoisomerism

Substances

  • Gels
  • Polymers