Pillar[5]arene-Based Visual Planar Chirality Switches with Variable Color Expression.

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Organic Chemistry

Background:

• Developing molecular systems with controllable chirality and macroscopic property changes is challenging.
• Existing dynamic chirality platforms and molecular designs are limited.

Purpose of the Study:

• To create novel chirality-controlled switches with reversible modulation of planar chirality.
• To establish a correlation between molecular conformation, guest inclusion, and macroscopic color changes.

Main Methods:

• Synthesis of two chirality-controlled switches, P5N-R and P5N-S.
• Investigating the reversible modulation of planar chirality using solvents, temperature, and guest molecules.
• Analyzing conformational changes and their impact on intramolecular hydrogen bonding and electronic properties.

Main Results:

• P5N-R and P5N-S exhibit reversible chirality control and color changes.
• Guest inclusion promotes a pillar conformation (pR-form), while exclusion favors a folded conformation (pS-form).
• Conformational changes alter intramolecular hydrogen bonds, affecting electron donation and causing distinct color changes.

Conclusions:

• A new strategy for constructing dynamic chiral switches with macroscopic property changes has been demonstrated.
• These switches offer a promising avenue for developing advanced, responsive chiral materials.
• The findings have significant implications for molecular-level chirality control systems.