Term: α-expulsion
https://doi.org/10.1351/goldbook.E00008

Definition:
A general reaction by which a group attached to the alpha carbon of an excited chromophore is expelled either as an odd electron species or as an anionic species. This reaction should be distinguished from an α-(alpha-)cleavage.

Related Terms:
1) chromophore (http://doi.org/10.1351/goldbook.C01076).
2) α-(alpha-)cleavage (http://doi.org/10.1351/goldbook.A00004).

Source: PAC, 1988, 60, 1055. 'Glossary of terms used in photochemistry (Recommendations 1988)' on page 1059 (https://doi.org/10.1351/pac198860071055)

Citation: 'α-expulsion' 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.E00008

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