Cucurbit[n]uril-based coordination chemistry: from simple coordination complexes to novel poly-dimensional coordination polymers

Abstract

Cucurbit[n]urils are a family of molecular container hosts bearing a rigid hydrophobic cavity and two identical carbonyl fringed portals. They have attracted much attention in supramolecular chemistry because of their superior molecular recognition properties in aqueous media. This review highlights the recent advances and challenges in the field of cucurbit[n]uril-based coordination chemistry. It not only presents progress in the knowledge of such macrocyclic compounds, which range from simple to complicated architectures, but also presents new routes of synthesis and their advantages in hybrid porous solids. The concept of structure "inducer" for their structural design to achieve predictable structures and controlled pores is described. The large pore sizes and hydrophobic cavities of these compounds that lead to unprecedented properties and potential applications are also discussed.

The Chaotropic Effect as an Assembly Motif in Chemistry

“…It should be noted that indications for the affinity of anions to hydrophobic binding sites existed early in the literature81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103 but were in part attributed to a putative hydrophobic (or lipophilic) property of large anions, implying the hydrophobic effect as driving force. The hydrophobic and chaotropic effect can and need to be conceptually distinguished for the reason stated above and also because the hydrophobic nature of a solute is subject to a conventional definition, which chaotropic ions do not fulfill.…”

“…It is not limited to the interaction with macrocyclic cavities (Figure 3) and the formation of inclusion complexes (Figure 4) but also applies similarly to the interactions with convex surfaces (Figure 6), which accounts for the intrinsic propensity of these large anions to form also exclusion complexes. Indeed, many studies have described their binding to the exterior of macrocycles,41, 64, 84, 86, 87, 88, 90, 91, 92, 93, 94, 154 where the chaotropic effect applies as well. Most of these cases involve macrocyclic hosts with relatively small cavity size, such that inclusion‐type complexes are not possible 41, 64, 94, 154.…”

Study of the Interaction between Two Kinds of Cucurbit [7]urils and 3-(2-Naphthyl)-alanine

“…图 1 主体 iQ [7]、Q [7]以及客体 L-NA、D-NA 的分子结构式 Figure 1 Structures of the hosts iQ [7], Q [7] and guests L-NA, D-NA 1 结果与讨论 Figure 2 1 H NMR spectra (400 MHz, D 2 O) of (A) guest L-NA (I) in the absence and in the presence of 0.49 equiv. (III), 1.02 equiv.…”

“…(III), 1.02 equiv. (II) of iQ [7] and iQ [7] (IV), and (B) guest L-NA (I) in the absence and in the presence of 0.48 equiv. (III), 1.05 equiv.…”

Label-Free Fluorescent Determination of Sunset Yellow in Soft Drinks Based on an Indicator-Displacement Assay

“…Upon displacement of the indicator, a change in signal is observed [2]. with crown ethers, cyclodextrins, and calixarenes, are the fourth-generation macrocyclic hosts that have played crucial roles in supramolecular chemistry in recent decades [11][12][13][14][15].…”