Term: envelope conformation
https://doi.org/10.1351/goldbook.E02152

Definition:
The conformation (of symmetry group Cs) of a five-membered ring in which four atoms are coplanar, and one atom (the flap) projects out of the plane. E02152.png

Related Terms:
1) conformation (http://doi.org/10.1351/goldbook.C01258).

Image: Not defined (https://goldbook.iupac.org/img/inline/E02152.png) 

Source: PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2208 (https://doi.org/10.1351/pac199668122193)

Citation: 'envelope conformation' 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.E02152

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