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 C and C fullerenes effectively, and the binding event can be regulated allosterically by the addition of methanol.

Enantioselective Molecular Recognition in a Flexible Self-Folding Cavitand.

We report a chiral deep cavitand receptor based on calix[5]arene stabilized by a cooperative network of hydrogen bonds and having a highly flexible structure. The cavitand displays enantioselective molecular recognition with a series of chiral quaternary ammonium salts, providing unprecedented stability ratios between the corresponding diastereomeric host-guest complexes. Molecular dynamics simulations corroborate the higher flexibility of the new host and the emergence of superior induced-fit behavior with regards to resorcin[4]arene derived self-folding cavitands.

A flexible self-folding receptor for coronene.

We report a conformationally flexible deep cavitand receptor based on calix[5]arene and stabilized by a cooperative network of hydrogen bonds. The receptor binds coronene selectively over smaller polycyclic aromatic hydrocarbons, but is flexible enough to adapt to a smaller guest that presents a complementary electron deficient surface. The unique dynamic properties of this system have been thoroughly studied by NMR spectroscopy and molecular dynamics (MD) simulations.