{Reference Type}: Journal Article
{Title}: A Strong Supramolecular Mechanophore with Controlled Mechanical Strength.
{Author}: Xia Y;Wang G;He C;Chen H;
{Journal}: Angew Chem Int Ed Engl
{Volume}: 0
{Issue}: 0
{Year}: 2024 Jun 13
{Factor}: 16.823
{DOI}: 10.1002/anie.202406738
{Abstract}: Supramolecular mechanophores typically exhibit much lower mechanical strengths than covalent counterparts, with strengths usually around 100 pN, which is significantly lower than the nN-scale strength of covalent bonds. Inspired by the slow dissociation kinetics of the cucurbit[7]uril (CB[7])-hexanoate-isoquinoline (HIQ) complex, we discovered that charge-dipole repulsion can be utilized to create strong supramolecular mechanophores. When activated at its -COO- state, the CB[7]-HIQ complex exhibits a high mechanical strength of ~700 pN, comparable to weak covalent bonds such as Au-S bonds or thiol-maleimide adducts. The strength of the CB[7]-HIQ complex can also be tuned with pH in a gradual manner, with a minimum value of ~150 pN at its -COOH state, similar to an ordinary supramolecular conjugate. This research may pave the way for the development of supramolecular architectures that combine the advantages of covalent and supramolecular systems.