Study on the coordination of cyclopentanocucurbit[5,6]uril with Fe, Co and Ni ions.

This paper reports the coordination of cyclopentanocucurbit[5]uril (CyPQ[5]) and cyclopentanocucurbit[6]uril (CyPQ[6]) with Fe(ClO), Co(ClO) and Ni(ClO). Single crystal X-ray diffraction analysis shows the metal ions are directly coordinated with the portal of the cucurbit[]uril to form a one-dimensional supramolecular chain or independent systems in the CyPQ[5]@Fe(ClO), CyPQ[5]@Co(ClO), CyPQ[6]@Co(ClO) and CyPQ[5]@Ni(ClO) complexes. In CyPQ[6]@Fe(ClO), the metal ion is not directly coordinated with the cucurbit[]uril portal, but after forming Fe(HO), it interacts with the cucurbit[]uril portal a hydrogen bond.

Host-guest modes and supramolecular frameworks of complexes of tetramethyl cucurbit[6]uril with 4-chloroaniline and 4,4'-diaminostilbene.

Since the first reportal on decamethylcucurbit[5]uril (MeQ[5]) in 1992, substituted cucurbit[]urils have attracted considerable research interest. In this study, the host-guest modes between the tetramethyl cucurbit[6]uril (TMeQ[6]) as a host and 4-chloroaniline and 4,4'-diaminostilbene (G1 and G2) as guests were investigated by single-crystal X-ray diffraction, NMR, ITC, UV-Vis spectrum, and MALDI-TOF mass spectrometry analyses. The experimental results showed that TMeQ[6] formed a 1 : 1 inclusion compound with G1, and the carbonyl portal of TMeQ[6] formed a 1 : 1 self-assembly with G2.

A study on the self-assembly mode and supramolecular framework of complexes of cucurbit[6]urils and 1-(4-methoxyphenyl)piperazine.

Self-assembly between symmetrical dicyclohexyl-substituted cucurbit[6]uril (abbreviated as (CyH)Q[6]) and cyclopentanocucurbit[6]uril (CyPQ[6]) as hosts and 1-(4-methoxyphenyl)piperazine (MeOPP) as a guest molecule has been studied by means of single-crystal X-ray diffraction analysis, NMR, MALDI-TOF mass spectrometry, and other characterization methods. The experimental results showed that the self-assembly was driven by the formation of exclusion complexes by the cucurbit[]uril and the guest, that is, supramolecular interaction between the negative charge of the cucurbit[]uril portals and a coordination polymer guest. Complexes were formed between the positive charge of the cucurbit[]uril outer wall and inorganic anions, thus generating self-assemblies with multi-dimensional and multi-level supramolecular frameworks.