Self-assembled hydrogen-bonded dimeric capsules with high kinetic stability

Abstract

With inclusion of a suitable guest, tetraurea derivatives of calix[4]arenes form dimers in apolar solvents (the picture shows a schematic representation of one such dimer with included benzene). The kinetic stability of these capsules can be drastically increased (by more than five orders of magnitude) by the attachment of bulky residues to the urea functions.