Endowing Polycyclic Aromatic Hydrocarbons with Induced Supramolecular Chirality by Engineering Cation-π Interaction

Area of Science:

• Supramolecular Chemistry
• Organic Chemistry
• Materials Science

Background:

• Cation-π interactions are vital noncovalent forces in biological and chemical systems.
• These interactions are seldom reported in chiral supramolecular systems.
• Controlling chirality in polycyclic aromatic hydrocarbons (PAHs) is challenging.

Purpose of the Study:

• To report a novel supramolecular chiral system utilizing cation-π interactions.
• To demonstrate the induction of supramolecular chirality in PAHs.
• To explore the role of cation-π interactions in forming supramolecular gels.

Main Methods:

• Co-assembly of a chiral cationic palladium complex (R-Pd) with 12 different PAHs.
• Formation of supramolecular gels in mixed solvents.
• Characterization using high-resolution mass spectrometry, 1H NMR, NOESY, XRD, and CD spectroscopy.

Main Results:

• Cation-π interaction was identified as the primary driving force for co-assembly.
• Supramolecular gels were successfully formed.
• Chirality was induced in the PAHs.
• Synergy with hydrogen bonds stabilized interactions in water-containing solvents, enhancing chiral induction.

Conclusions:

• Cation-π interactions can effectively drive the formation of chiral supramolecular structures.
• This study provides a proof-of-principle for using cation-π interactions to induce chirality in PAHs.
• The findings offer a new strategy for designing chiral materials and understanding molecular recognition.