An AAA-DDD triply hydrogen-bonded complex easily accessible for supramolecular polymers

Area of Science:

• Supramolecular Chemistry
• Materials Science

Background:

• Complementary hydrogen-bonded complexes with segregated donors and acceptors exhibit enhanced stability due to attractive secondary interactions.
• The AAA-DDD sequence, where A represents an acceptor and D represents a donor, is recognized as a particularly stable triply hydrogen-bonded motif.

Purpose of the Study:

• To synthesize and characterize the AAA-DDD system for potential use in hydrogen-bonded functional materials.
• To explore the accessibility of AAA-DDD sequences for stimuli-responsive applications.

Main Methods:

• Synthesis of AAA and DDD components utilizing Hantzsch pyridine synthesis and Friedländer annulation, starting from 4-methoxybenzaldehyde.
• Determination of the association constant via fluorescence titration in chloroform at room temperature.
• Solid-state structural analysis to determine molecular conformation.

Main Results:

• The synthesized AAA-DDD system demonstrated a high association constant of 2.09×10^7 M⁻¹ in chloroform.
• Structural analysis revealed that the AAA and DDD components adopt a non-coplanar V-shape in the solid state.
• Development of supramolecular polymers based on the AAA-DDD triply hydrogen-bonded motif.

Conclusions:

• The study successfully synthesized and characterized a stable AAA-DDD system, demonstrating its potential for creating functional materials.
• The developed synthetic routes make AAA-DDD sequences readily accessible, paving the way for their integration into stimuli-responsive materials.