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Updated: Jan 19, 2026

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Radial Hetero[5]catenanes: Peripheral Isomer Sequences of the Interlocked Macrocycles
Antony Wing Hung Ng1, Chi-Chung Yee1, Ho Yu Au-Yeung1
1Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
Abstract:
A pair of radial [5]catenanes, with either an isomeric cyclic -AABB- or -ABAB- type sequence of the interlocked β-cyclodextrin (β-CD) and cucurbit[6]uril (CB[6]) units, has been efficiently synthesized. Because of a marked difference in the binding strength and interlocking sequence of the peripheral macrocycles, interesting sequence-dependent properties, characteristic of mechanically bonded macrocycles, were realized. Variable-temperature 1 H NMR studies showed that the -ABAB- isomer has a more independent β-CD dynamic, whereas the β-CD motions in the -AABB- isomer are coupled. Dynamics of the pH-insensitive β-CD can also be further modulated upon base-triggered mobilization of the CB[6]. These unique properties of the mechanical bond expressed in a sequence-specific fashion and the transmission of the control on the macrocycle dynamics from one interlocked component to another, highlight the potential of similar complex hetero[n]catenanes in the design of advanced, multicomponent molecular machines.
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