Rigid chiral carbocyclic clefts as building blocks for the construction of new supramolecular hosts

The synthesis and resolution of two chiral carbocyclic cleft molecules containing carbonyl groups on the periphery of the cavity are reported. These compounds are reminiscent of Troger's base but contain a smaller cleft and additional carbonyl (or alcohol) groups. X-ray crystal structures of the dibromo and dimethyl derivatives show that the dihedral angle between the two aromatic rings is 79° and 85° respectively. The dibromo derivative provides entry into new supramolecular hosts, via introduction of additional recognition groups into the cleft molecules.