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π-Stacking Stopper-Macrocycle Stabilized Dynamically Interlocked [2]Rotaxanes.

ABSTRACT: The synthesis of mechanically interlocked molecules is valuable due to their unique topologies. With π-stacking intercomponent interaction, e.g., phenanthroline and anthracene, novel [2]rotaxanes have been synthesized by dynamic imine clipping reaction. Their X-ray crystal structures indicate the π-stackings between the anthracene moiety (stopper) on the thread and the (hetero)aromatic rings at the macrocycle of the rotaxanes. Moreover, the length of glycol chains affects the extra π-stacking intercomponent interactions between the phenyl groups and the dimethoxy phenyl groups on the thread. Dynamic combinatorial library has shown at best 84% distribution of anthracene-threaded phenanthroline-based rotaxane, coinciding with the crystallography in that the additional π-stacking intercomponent interactions could increase the thermodynamic stability and selectivity of the rotaxanes.

SUBMITTER: Chan SM

PROVIDER: S-EPMC8347712 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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π-Stacking Stopper-Macrocycle Stabilized Dynamically Interlocked [2]Rotaxanes.

Chan Sing-Ming SM Tang Fung-Kit FK Lam Ching-Yau CY Kwan Chak-Shing CS Hau Sam C K SCK Leung Ken Cham-Fai KC

Molecules (Basel, Switzerland) 20210803 15

The synthesis of mechanically interlocked molecules is valuable due to their unique topologies. With π-stacking intercomponent interaction, e.g., phenanthroline and anthracene, novel [2]rotaxanes have been synthesized by dynamic imine clipping reaction. Their X-ray crystal structures indicate the π-stackings between the anthracene moiety (stopper) on the thread and the (hetero)aromatic rings at the macrocycle of the rotaxanes. Moreover, the length of glycol chains affects the extra π-stacking in ...[more]

PMID: 34361858

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