Semitubular Aromatic Fragment of Schwarzite P192: A Conserved Structural Motif with Two Embedded Octagons

Area of Science:

• Materials Science
• Organic Chemistry
• Nanotechnology

Background:

• Molecular carbons with negative curvature are key for synthesizing schwarzite carbon.
• Precise synthesis of such structures remains a significant challenge in materials science.

Purpose of the Study:

• To report the synthesis of a novel semitubular molecule with negative curvature.
• To investigate its structural and electronic properties and its potential as a schwarzite substructure.

Main Methods:

• Scholl oxidation of a twisted bismacrocyclic precursor.
• X-ray crystallography for structural elucidation.
• Experimental and theoretical investigations for flexibility analysis.
• Root-mean-square deviation (RMSD) analysis for structural matching.

Main Results:

• Successful synthesis of a semitubular molecule with two [8]circulene moieties, exhibiting significant π-system bending.
• X-ray crystallography confirmed a highly warped structure matching Schwarzite P192 substructure.
• Demonstrated flexibility of the π-skeleton and potential for forming cocrystalline assemblies with C60 molecules.

Conclusions:

• The synthesized semitube serves as a viable molecular model for schwarzite carbon.
• This work provides a pathway for designing and synthesizing novel negatively curved molecular carbon materials.
• The materials exhibit potential for applications requiring high porosity and π-conjugation.