Intermolecular hydrogen bonding in calix[5]arene derived cavitands regulates the molecular recognition of fullerenes

We present a readily available calix[5]arene derived cavitand receptor that is stabilized in the closed cone conformer through intermolecular hydrogen bonding with methanol molecules. The receptor features a highly spherical aromatic surface that binds C60 and C70 fullerenes effectively, and the binding event can be regulated allosterically by the addition of methanol. A flexible cavitand host for fullerenes based on calix[5]arene is presented. Stabilisation by intermolecular hydrogen bonding to methanol results in a more structured environment, providing 10-fold enhancement of the association constant with C60.

Automated summary

We introduce a calix[5]arene derived cavitand receptor stabilized in the closed cone conformation through intermolecular hydrogen bonding with methanol. The receptor possesses a highly spherical aromatic surface that can effectively bind C60 and C70 fullerenes, and the binding can be regulated allosterically by methanol addition. A flexible cavitand host based on calix[5]arene for fullerenes is presented, where stabilization through intermolecular hydrogen bonding with methanol leads to a more structured environment and a 10-fold enhancement of the association constant with C60.