Velcrands with snaps and their conformational control

Area of Science:

• Supramolecular Chemistry
• Materials Science

Background:

• Velcrands are molecules that dimerize through intermolecular forces.
• Resorcinarene-based cavitands are known for their structural versatility.

Purpose of the Study:

• To synthesize a novel class of self-folding velcrands.
• To investigate their dimerization behavior and conformational changes.
• To explore their potential for noncovalent polymer assembly.

Main Methods:

• Preparation of self-folding velcrands incorporating hydrogen bonding sites on a resorcinarene-based cavitand.
• Investigation of dimerization through solvophobic interactions and hydrogen bonds.
• Analysis of conformational changes induced by solvent polarity (aromatic solvents/CDCl3 vs. [D6]DMSO).

Main Results:

• A novel class of self-folding velcrands capable of dimerization was successfully prepared.
• Eight hydrogen bonds act as 'snaps' to stabilize the dimer.
• Solvent polarity was shown to control the equilibrium between extended (D2d) and deep cavity (C4v) conformations.
• The internal cavity size and shape undergo dramatic reorganization with changes in solvent polarity.

Conclusions:

• The synthesized velcrands exhibit controllable dimerization and conformational switching.
• The observed properties make them suitable for the assembly of noncovalent polymeric materials.
• This work expands the toolkit for designing sophisticated supramolecular structures.