%0 Journal Article
%T A Strong Supramolecular Mechanophore with Controlled Mechanical Strength.
%A Xia Y
%A Wang G
%A He C
%A Chen H
%J Angew Chem Int Ed Engl
%V 0
%N 0
%D 2024 Jun 13
%M 38869842
%F 16.823
%R 10.1002/anie.202406738
%X 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.