Title: planar chirality
Long Title: IUPAC Gold Book - planar chirality
DOI: 10.1351/goldbook.P04681
Status: current

Definition
Term used by some authorities to refer to stereoisomerism resulting from the arrangement of out-of-plane groups with respect to a plane (chirality plane). It is exemplified by the atropisomerism of (E)-cyclooctene (chiral plane = double bond and attached atoms) or monosubstituted paracyclophane (chiral plane = substituted ring). The configuration of molecular entities possessing planar chirality is specified by the stereodescriptors \(R_{\rm{p}}\) and \(S_{\rm{p}}\) (or \(P\) and \(M\)). 

Related Terms
- atropisomerism: https://goldbook.iupac.org//terms/view/A00511
- chiral: https://goldbook.iupac.org//terms/view/C01057
- chirality: https://goldbook.iupac.org//terms/view/C01058
- plane: https://goldbook.iupac.org//terms/view/C01062
- stereoisomerism: https://goldbook.iupac.org//terms/view/S05983

Source
- PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2213 (https://doi.org/10.1351/pac199668122193)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/P04681/html
- json: https://goldbook.iupac.org/terms/view/P04681/json
- xml: https://goldbook.iupac.org/terms/view/P04681/xml

Citation: Citation: 'planar chirality' 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.P04681
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Accessed: 2026-06-27T22:26:24+00:00