Work

Enantio- and diastereoselective synthesis of multi-helical nanographenes

Year: 2026

Type: article

Abstract: Nanographenes, composed of two-dimensionally fused planar polycyclic aromatics, are promising candidates for organic optoelectronic applications due to their high chemical and thermal stability and efficient charge transport. However, their high planarity often leads to aggregation and poor solubility. Introducing helicene units at the nanographene periphery is an effective strategy to enhance solubility and impart chiroptical functionality. Here we report the enantio- and diastereoselective synthesis of hexabenzocoronene-based helical nanographenes bearing up to eight uniformly aligned helicene units via enantioselective [2+2+2] cycloaddition followed by a diastereoselective Scholl reaction. Systematic variation of aryl substituents within this synthetic platform affords a family of multi-helical nanographenes with tunable photophysical and chiroptical properties. A helical nine-armchair graphene nanoribbon bearing six peripheral helicene units is also accessible, exhibiting near-infrared emission with high fluorescence quantum yield and a distinct chiroptical response. Together, these results demonstrate a versatile platform for constructing complex chiral nanographenes with precise helicity control. A modular stereoselective synthetic strategy enables precise control over the stereochemistry of multiple helicene units in nanographenes. This approach provides access to hexabenzocoronenes and graphene nanoribbons bearing up to eight uniformly aligned helicenes, with systematically tunable photophysical, chiroptical and near-infrared emissive properties for advanced optoelectronic materials.

Source: Nature Synthesis

DOI: 10.1038/s44160-026-01155-9