Term: proton transfer reaction
https://doi.org/10.1351/goldbook.P04915

Definition:
A chemical reaction, the main feature of which is the intermolecular or intramolecular transfer of a proton (hydron) from one binding site to another. For example: P04915.png In the detailed description of proton transfer reactions, especially of rapid proton transfers between electronegative atoms, it should always be specified whether the term is used to refer to the overall process (including the more-or-less encounter-controlled formation of a hydrogen bonded complex and the separation of the products; see microscopic diffusion control) or just to the proton transfer event (including solvent rearrangement) by itself.

Related Terms:
1) autoprotolysis (http://doi.org/10.1351/goldbook.A00531).
2) tautomerism (http://doi.org/10.1351/goldbook.T06252).
3) chemical reaction (http://doi.org/10.1351/goldbook.C01033).
4) intermolecular (http://doi.org/10.1351/goldbook.I03098).
5) intramolecular (http://doi.org/10.1351/goldbook.I03130).
6) hydron (http://doi.org/10.1351/goldbook.H02904).
7) binding site (http://doi.org/10.1351/goldbook.B00649).
8) encounter-controlled (http://doi.org/10.1351/goldbook.E02089).
9) microscopic diffusion control (http://doi.org/10.1351/goldbook.M03912).
10) proton (http://doi.org/10.1351/goldbook.P04906).
11) rearrangement (http://doi.org/10.1351/goldbook.R05194).

Image: Not defined (https://goldbook.iupac.org/img/inline/P04915.png) 

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1153 (https://doi.org/10.1351/pac199466051077)

Citation: 'proton transfer reaction' 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.P04915

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