Term: Lewis base
https://doi.org/10.1351/goldbook.L03511

Definition:
A molecular entity (and the corresponding chemical species) able to provide a pair of electrons and thus capable of coordination to a Lewis acid, thereby producing a Lewis adduct.

Related Terms:
1) molecular entity (http://doi.org/10.1351/goldbook.M03986).
2) chemical species (http://doi.org/10.1351/goldbook.CT01038).
3) coordination (http://doi.org/10.1351/goldbook.C01329).
4) lewis acid (http://doi.org/10.1351/goldbook.L03508).
5) lewis adduct (http://doi.org/10.1351/goldbook.L03510).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1135 (https://doi.org/10.1351/pac199466051077)

Citation: 'Lewis base' 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.L03511

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