Synthesis of a [6]rotaxane with singly threaded γ-cyclodextrins as a single stereoisomer.

Beilstein J Org Chem

Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.

Published: August 2019

A series of hetero [4]-, [5]- and [6]rotaxanes containing both cucurbit[6]uril (CB[6]) and γ-cyclodextrin (γ-CD) as the macrocyclic components have been synthesized via a threading-followed-by-stoppering approach. Due to the orthogonal binding of CB[6] to ammonium and γ-CD to biphenylene/tetra(ethylene glycol), the []rotaxanes display a specific sequence of the interlocked macrocycles. In addition, despite of the asymmetry of γ-CD with respect to the orthogonal plane of the axle, only one stereoisomer of the [6]rotaxane was obtained.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6693375PMC
http://dx.doi.org/10.3762/bjoc.15.177DOI Listing

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