Self-complementary quadruply hydrogen-bonded duplexes based on imide and urea units

Area of Science:

• Supramolecular Chemistry
• Organic Chemistry
• Materials Science

Background:

• Hydrogen bonding is crucial for molecular self-assembly.
• Imide-urea motifs offer unique hydrogen bonding capabilities.

Purpose of the Study:

• To investigate the self-assembly of quadruply hydrogen-bonded imide-urea duplexes.
• To evaluate the stability and factors influencing their association.
• To explore their potential in supramolecular architecture.

Main Methods:

• Synthesis of imide-urea based association units.
• Quadruple hydrogen bonding analysis.
• (1)H NMR dilution experiments to determine association constants.

Main Results:

• Formation of stable homodimers through bifurcated hydrogen bonds.
• High dimerization constants (K(dim) > 10(5) M(-1) in CDCl(3)) in apolar solvents.
• Enhanced association affinity with electron-withdrawing substituents.

Conclusions:

• Imide-urea duplexes exhibit robust self-assembly via quadruple hydrogen bonding.
• Tunable association strength through electronic modifications.
• Potential building blocks for advanced supramolecular materials.