Term: carbanion
https://doi.org/10.1351/goldbook.C00804

Definition:
Generic name for anions containing an even number of electrons and having an unshared pair of electrons on a tervalent carbon atom (e.g. Cl3C− or HC≡C− ) or — if the ion is mesomeric (see mesomerism) — having at least one significant contributing structure with an unshared pair of electrons on a tervalent carbon atom, for example: C00804-1.png

Related Terms:
1) radical ion (http://doi.org/10.1351/goldbook.R05073).
2) mesomerism (http://doi.org/10.1351/goldbook.M03845).
3) contributing structure (http://doi.org/10.1351/goldbook.C01309).

Image: Not defined (https://goldbook.iupac.org/img/inline/C00804-1.png) 

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1092 (https://doi.org/10.1351/pac199466051077)

Citation: 'carbanion' 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.C00804

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