Term: nucleophile (nucleophilic)
https://doi.org/10.1351/goldbook.N04249

Definition:
A nucleophile (or nucleophilic reagent) is a reagent that forms a bond to its reaction partner (the electrophile) by donating both bonding electrons. A 'nucleophilic substitution reaction' is a heterolytic reaction in which the reagent supplying the entering group acts as a nucleophile. For example: N04249.png The term 'nucleophilic' is also used to designate the apparent polar character of certain radicals, as inferred from their higher relative reactivity with reaction sites of lower electron density. Nucleophilic reagents are Lewis bases.

Related Terms:
1) reagent (http://doi.org/10.1351/goldbook.R05190).
2) substitution reaction (http://doi.org/10.1351/goldbook.S06078).
3) entering group (http://doi.org/10.1351/goldbook.E02130).
4) electron density (http://doi.org/10.1351/goldbook.E01986).
5) electrophile (http://doi.org/10.1351/goldbook.E02020).
6) heterolytic (http://doi.org/10.1351/goldbook.H02809).
7) radicals (http://doi.org/10.1351/goldbook.R05066).
8) lewis bases (http://doi.org/10.1351/goldbook.L03511).

Image: Not defined (https://goldbook.iupac.org/img/inline/N04249.png) 

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)

Citation: 'nucleophile (nucleophilic)' 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.N04249

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