A Trefoil Macrocycle Synthesized by 3-Fold Benzannulation

Area of Science:

• Organic Chemistry
• Supramolecular Chemistry
• Materials Science

Background:

• Macrocyclic compounds are fundamental building blocks in supramolecular chemistry.
• Developing novel molecular architectures with unique symmetries and self-assembly properties is a key research area.
• Copper-catalyzed reactions offer efficient pathways for constructing complex organic molecules.

Purpose of the Study:

• To synthesize a novel trefoil-shaped molecular architecture.
• To investigate the conformational properties and symmetry of the synthesized molecule.
• To explore the supramolecular assembly behavior of the trefoil macrocycle.

Main Methods:

• Synthesis via a 3-fold copper-catalyzed [4 + 2] benzannulation reaction.
• Density Functional Theory (DFT) calculations for conformational analysis.
• Single-crystal X-ray diffraction for structural determination.

Main Results:

• Successful synthesis of a trefoil-shaped molecule composed of three conjugated macrocycles.
• DFT calculations predicted a D3-symmetric stable conformation.
• X-ray crystallography confirmed the D3-symmetry and revealed enantiomeric forms.
• Observation of honeycomb-like supramolecular structures in the solid state.

Conclusions:

• The study presents a new method for constructing complex macrocyclic architectures.
• The trefoil macrocycle demonstrates predictable symmetry and interesting self-assembly capabilities.
• The findings contribute to the design of novel functional organic materials.