Title: ring reversal
Long Title: IUPAC Gold Book - ring reversal
DOI: 10.1351/goldbook.R05397
Status: current

Definition
The interconversion by rotation about single bonds (coupled with angle deformation in the transition state) of cyclic conformers having equivalent ring shapes (e.g. chair → chair) though not necessarily equivalent spatial positions of substituents (e.g. equatorial → axial).

Related Terms
- angle: https://goldbook.iupac.org/terms/view/A00346
- axial: https://goldbook.iupac.org/terms/view/A00546
- chair: https://goldbook.iupac.org/terms/view/C00965
- equatorial: https://goldbook.iupac.org/terms/view/E02174
- transition state: https://goldbook.iupac.org/terms/view/T06468

Source
- PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2217 (https://doi.org/10.1351/pac199668122193)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/R05397/html
- json: https://goldbook.iupac.org/terms/view/R05397/json
- xml: https://goldbook.iupac.org/terms/view/R05397/xml

Citation: Citation: 'ring reversal' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.R05397
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Accessed: 2026-05-10T05:00:09+00:00