Title: nucleophilicity
Long Title: IUPAC Gold Book - nucleophilicity
DOI: 10.1351/goldbook.N04251
Status: current

Definition
The property of being nucleophilic.The relative reactivity of a nucleophilic reagent. (It is also sometimes referred to as 'nucleophilic power'.) Qualitatively, the concept is related to Lewis basicity. However, whereas Lewis basicity is measured by relative equilibrium constants:  nucleophilicity of a Lewis base is measured by relative rate constants of different nucleophilic reagents towards a common substrate, most commonly involving formation of a bond to carbon: 

Related Terms
- Lewis base: https://goldbook.iupac.org/terms/view/L03511
- Lewis basicity: https://goldbook.iupac.org/terms/view/L03512
- Ritchie equation: https://goldbook.iupac.org/terms/view/R05402
- Swain–Scott equation: https://goldbook.iupac.org/terms/view/S06201
- electrophilicity: https://goldbook.iupac.org/terms/view/E02021
- nucleophilic: https://goldbook.iupac.org/terms/view/N04249
- power: https://goldbook.iupac.org/terms/view/P04792
- rate constants: https://goldbook.iupac.org/terms/view/O04322
- reagent: https://goldbook.iupac.org/terms/view/R05190

Source
- PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1146 (https://doi.org/10.1351/pac199466051077)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/N04251/html
- json: https://goldbook.iupac.org/terms/view/N04251/json
- xml: https://goldbook.iupac.org/terms/view/N04251/xml

Citation: Citation: 'nucleophilicity' 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.N04251
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Accessed: 2026-05-11T12:23:23+00:00