Coordination of Alkaline Earth Metal Ions in the Inverted Cucurbit[7]uril Supramolecular Assemblies Formed in the Presence of [ZnCl 4 ] 2− and [CdCl 4 ] 2−

A convenient method to isolate inverted cucurbit[7]uril ( i Q[7]) from a mixture of water‐soluble Q[ n ]s was established by eluting the soluble mixture of Q[ n ]s on a Dowex (H + form) column so that i Q[7] could be selected as a ligand for coordination and supramolecular assembly with alkaline earth cations (AE 2+ ) in aqueous HCl solutions in the presence of [ZnCl 4 ] 2− and [CdCl 4 ] 2− anions as structure‐directing agents. Single‐crystal X‐ray diffraction analysis revealed that both i Q[7]–AE 2+ –[ZnCl 4 ] 2− –HCl and i Q[7]–AE 2+ –[CdCl 4 ] 2− –HCl interaction systems yielded supramolecular assemblies, in which the [ZnCl 4 ] 2− and [CdCl 4 ] 2− anions presented a honeycomb effect, and this resulted in the formation of linear i Q[7]/AE 2+ coordination polymers through outer‐surface interactions of Q[ n ]s.