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Diastereoselective Amplification of a Mechanically Chiral [2]Catenane.

ABSTRACT: Achiral [2]catenanes composed of rings with inequivalent sides may adopt chiral co-conformations. Their stereochemistry depends on the relative orientation of the interlocked rings and can be controlled by sterics or an external stimulus (e.g., a chemical stimulus). Herein, we have exploited this stereodynamic property to amplify a mechanically chiral (P)-catenane upon binding to (R)-1,1'-binaphthyl 2,2'-disulfonate, with a diastereomeric excess of 85%. The chirality of the [2]catenane was ascertained in the solid state by single crystal X-ray diffraction and in solution by NMR and CD spectroscopies. This study establishes a robust basis for the development of a new synthetic approach to access enantioenriched mechanically chiral [2]catenanes.

SUBMITTER: Caprice K

PROVIDER: S-EPMC8397304 | biostudies-literature |

REPOSITORIES: biostudies-literature

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