Term: topomerization
https://doi.org/10.1351/goldbook.T06396

Definition:
The identity reaction leading to exchange of the positions of identical ligands. The indistinguishable molecular entities involved are called topomers. For example in the reaction below the two identical ligating atoms Na and Nb are interchanged by rotation about the C-aryl bond but may be identified by NMR spectroscopy. This is a degenerate isomerization. T06396.png

Related Terms:
1) identity reaction (http://doi.org/10.1351/goldbook.I02940).
2) ligands (http://doi.org/10.1351/goldbook.L03518).
3) spectroscopy (http://doi.org/10.1351/goldbook.S05848).
4) isomerization (http://doi.org/10.1351/goldbook.I03295).

Image: Not defined (https://goldbook.iupac.org/img/inline/T06396.png) 

Source: PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2220 (https://doi.org/10.1351/pac199668122193)

Citation: 'topomerization' 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.T06396

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