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

ABSTRACT: A series of hetero [4]-, [5]- and [6]rotaxanes containing both cucurbit[6]uril (CB[6]) and ?-cyclodextrin (?-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 ?-CD to biphenylene/tetra(ethylene glycol), the [n]rotaxanes display a specific sequence of the interlocked macrocycles. In addition, despite of the asymmetry of ?-CD with respect to the orthogonal plane of the axle, only one stereoisomer of the [6]rotaxane was obtained.

SUBMITTER: Man JYH

PROVIDER: S-EPMC6693375 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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

Man Jason Yin Hei JYH Au-Yeung Ho Yu HY

Beilstein journal of organic chemistry 20190801

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 [<i>n</i>]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 on ...[more]

PMID: 31467603

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