Search

Herein, we report the supramolecular self‐assembly of fully substituted cyclopentano cucurbit[5]uril (CyP5Q[5]) and cucurbit[6]uril (CyP6Q[6]) with Cu(ClO4)2 and Zn(ClO4)2 in a solution of formic acid. Single crystal X‐ray diffraction analysis showed that CyP5Q[5]‐Cu(ClO4)2 forms a W‐type molecular capsule complex and CyP5Q[5]‐Zn(ClO4)2 forms alternate Z‐type and V‐type molecular capsule complexes. Both CyP6Q[6]‐Cu(ClO4)2 and CyP6Q[6]‐Zn(ClO4)2 form Z‐type molecular capsule complexes. These two coordination systems have the same unit cell parameters and are isomorphic complexes. In these four systems the ClO4– ions are coordinated around the cucurbituril via ion‐dipole interactions and induce the self‐assembly of the cucurbituril and metal ions. [ABSTRACT FROM AUTHOR]

In this study, fully substituted cyclopentano cucurbit[5]uril (CyP 5 Q[5]) were coordinated with an alkaline earth cations (AE 2+ ) in the presence of tetrachlorozincate anions ([ZnCl 4 ] 2− ). Single-crystal X-ray diffraction analysis revealed that the CyP 5 Q[5]–Mg 2+ –[ZnCl 4 ] 2− –HCl interaction system yielded an Mg 2+ /Cl − @CyP 5 Q[5]-type molecular bowl, with a chloride anion in the cavity of the CyP 5 Q[5] moiety. The CyP 5 Q[5]–Ca 2+ and Sr 2+ –[ZnCl 4 ] 2− –HCl interaction systems yielded isolated AE 2+ /CyP 5 Q[5]/AE 2+ -type molecular capsules, again with a chloride anion in the CyP 5 Q[5] cavity. A honeycomb effect was evident in all three systems, in which the of the [ZnCl 4 ] 2− anions surround the CyP 5 Q[5] molecules through outer surface interactions between Q[n] and electrostatic interactions with AE 2+ cations, resulting in the formation of porous supramolecular assemblies. Direct coordination between Ba 2+ and CyP 5 Q[5] yielded zigzag coordination polymers. The CyP 5 Q[5]/AE 2+ -based supramolecular assemblies (AE = Mg, Ca, Sr, Ba) presented different porous conformations and displayed differential absorption of volatile compounds. [ABSTRACT FROM AUTHOR]

Coordination of fully substituted cyclopentano cucurbit[5]uril (CyP 5 Q[5]) with an alkali cation (A + ) in the presence of tetrachloridezicate anions was investigated. Single-crystal X-ray diffraction analysis revealed that the CyP 5 Q[5]–Na + and K + –[ZnCl 4 ] 2 − –HCl interaction systems yielded an A + /Cl − @CyP 5 Q[5]/A + -type molecular capsule, and that a chloride anion was included in the cavity of the CyP 5 Q[5] molecule. [ZnCl 4 ] 2− anions were not involved in direct coordination with the A + /Cl − @CyP 5 Q[5]/A + capsule. The CyP 5 Q[5]–Rb + and Cs + –[ZnCl 4 ] 2 − –HCl interaction systems yielded an A + /CyP 5 Q[5]/A + -type molecular capsule shell, and no chloride anions were included in the cavity of the CyP 5 Q[5] molecule. [ZnCl 4 ] 2− anions directly interacted with coordinated Rb + or Cs + cations through electrostatic interaction, and [ZnCl 4 ] 2− anions in particular played the role of linkers, resulting in the formation of a linear supramolecular assembly ⋯[ZnCl 4 ] 2 − –A + /Cl − @CyP 5 Q[5]/A + –[ZnCl 4 ] 2 − –A + /Cl − @CyP 5 Q[5]/A + ⋯. Close inspection revealed that the obtained CyP 5 Q[5]/A + -based supramolecular assemblies (A = Na, K, Rb, Cs) presented different porous conformation and could show different absorption properties. [ABSTRACT FROM AUTHOR]