Term: ring reversal (ring inversion)
https://doi.org/10.1351/goldbook.R05397

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:
1) angle (http://doi.org/10.1351/goldbook.A00346).
2) transition state (http://doi.org/10.1351/goldbook.T06468).
3) chair (http://doi.org/10.1351/goldbook.C00965).
4) equatorial (http://doi.org/10.1351/goldbook.E02174).
5) axial (http://doi.org/10.1351/goldbook.A00546).

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

Citation: 'ring reversal (ring inversion)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.R05397

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