A Study on the Coordination of Fully Substituted Cyclopentano Cucurbit[5, 6]uril with Copper and Zinc Ions

Abstract

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.

Study on the coordination of cyclopentanocucurbit[5,6]uril with Fe3+, Co2+ and Ni2+ ions

“…So far, the main alkyl-modied Q[n]s reported are methyl-substituted Q[n] s, [14][15][16] cyclopentyl-substituted Q[n]s, 9,10,[17][18][19] cyclohexylsubstituted Q[n]s [20][21][22] and cyclobutyl-substituted Q[n]s. 23 In previous work, the coordination of CyP5Q [5] with alkali metal cations (A + ) 24 and alkaline earth metal cations (AE 2+ ), 25 CyP6Q [6] with alkaline earth metal cations (AE 2+ ) 26 and lanthanides (Ln 3+ ) 27 with [ZnCl 4 ] 2À as an inducer are investigated. In 2019, Zhao et al reported the coordination of cyclopentyl-substituted Q[n]s with Cu and Zn ions, 28 and in 2021, Ma et al reported the supramolecular self-assembly of CyP5Q [5] with heavy metal ionic compounds (CoCl 2 , CrCl 3 , HgCl 2 , Pb(ClO 4 ) 2 ) under acidic conditions, 29 extending the coordination studies of cyclopentyl-substituted Q[n]s with metal ions. In this paper, the cyclopentyl-substituted Q[n]s CyP5Q [5] and CyP6Q [6] are selected as organic ligands and the coordination modes with iron, cobalt and nickel ions are investigated, respectively, improving the model of the interaction of cyclopentyl-substituted Q[n]s with transition metals, from which the formed supramolecular framework structures are expected to have better application prospects in the elds of gas molecule adsorption, drug delivery, supramolecular chemistry and coordination chemistry.…”

Preparation and characterization of a new type of symmetrical dicyclopentyl substituted cucurbit[6]uril

“…Cyclopentyl substituted cucurbituril [24][25][26][27] is a new type of modified cucurbituril with good solubility in both organic and aqueous phases, which is not available in ordinary cucurbiturils. In the past few years, the synthesis and various properties of cyclopentyl substituted cucurbituril have been reported successively.…”