Title: pseudorotaxane
Long Title: IUPAC Gold Book - pseudorotaxane
DOI: 10.1351/goldbook.13972
Status: current

Definition
Rotaxane-like molecular assembly in which the threading component(s) has(have) ends small enough to permit threading or dethreading of the macrocyclic component(s).

Notes
1) The stability of a pseudorotaxane may arise not only from spatially hindered dethreading of its components, but also from interaction between threading and macrocyclic components, e.g., donor-acceptor or electrostatic or coordination (see recognition site).
2) Pseudorotaxanes in which only one end of a threading component is capped with a stopper are sometimes called "semirotaxanes" or "half-capped pseudorotaxanes".

Related Terms
- macrocyclic component(s): https://goldbook.iupac.org//terms/view/13965
- threading component(s): https://goldbook.iupac.org//terms/view/13985

Source
- PAC, 2012, 84, 2135. 'Terminology and nomenclature for macromolecular rotaxanes and pseudorotaxanes (IUPAC Recommendations 2012)' on page 2140 (https://doi.org/10.1351/PAC-REC-11-10-15)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13972/html
- json: https://goldbook.iupac.org/terms/view/13972/json
- xml: https://goldbook.iupac.org/terms/view/13972/xml

Citation: Citation: 'pseudorotaxane' 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.13972
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Accessed: 2026-05-09T17:42:46+00:00