A Writhed Möbius Nanobelt Derived from [7]Helicene

Area of Science:

• Supramolecular Chemistry
• Organic Synthesis
• Nanotechnology

Background:

• Möbius aromaticity in nanostructures is of significant interest.
• Designing complex molecular architectures with unique electronic properties is a key challenge.

Purpose of the Study:

• To synthesize a novel Möbius nanobelt using specific building blocks.
• To investigate the structural, electronic, and chiroptical properties of the synthesized nanobelt.

Main Methods:

• Synthesis via nucleophilic aromatic substitution and reductive aromatization/oxidation.
• Structural characterization using X-ray crystallography.
• Spectroscopic analysis (1H NMR) and theoretical calculations.

Main Results:

• A novel Möbius nanobelt was successfully synthesized and structurally confirmed.
• The nanobelt exhibits distinct 1H NMR signal behavior compared to its macrocyclic precursor due to restricted rotation.
• Theoretical calculations revealed localized aromatic ring currents, not global ones.
• Enantiopure nanobelts were obtained, showing a notable absorption dissymmetry factor.

Conclusions:

• The synthesized Möbius nanobelt possesses unique structural and electronic properties.
• The arrangement of substituents significantly influences symmetry reflection in NMR spectra.
• The study demonstrates a pathway to enantiopure Möbius nanostructures with potential chiroptical applications.