Coordination and supramolecular assemblies of mono-hydroxylated octamethylcucurbit[6]uril with alkali and alkaline earth metal ions in the presence of polychloride cadmium anions

The interactions of alkali metal (A+ = Na+, K+, Rb+, Cs+) and alkaline earth metal cations (AE2+ = Mg2+, Ca2+, Sr2+, Ba2+) with mono-hydroxylated octamethylcucurbit[6]uril {(OH)OMeQ[6]} have been investigated in the presence of polychloride cadmium anions as structure-directing agents. Single-crystal X-ray diffraction analysis has revealed that the interactions of (OH)OMeQ[6] with A+ or AE2+ cations results in the formation of (OH)OMeQ[6]-based coordination complexes from (OH)OMeQ[6]–ACl or AECl2–CdCl2–HCl systems, in which Cd2+ cations form [Cd2Cl8]4− or [CdCl4]2− anions that serve as structure-directing agents in the formation of (OH)OMeQ[6]/A+ or AE2+-based supramolecular assemblies.