Title: photorearrangement
Long Title: IUPAC Gold Book - photorearrangement
DOI: 10.1351/goldbook.PT07460
Status: current

Definition
Photoisomerization involving changes in the arrangement of the atoms within the molecular species. It may lead to unstable isomers that react further by, e.g., dehydrogenation, deprotonation, or other reactions.

Note
Examples are photorearrangements of alkenes (other than cis-trans photoisomerization), of cyclohex-2-enones, of endoperoxides, of thioarenes, the di-π-methane rearrangement and others.

Related Terms
- alkenes: https://goldbook.iupac.org//terms/view/A00224
- di-π-methane rearrangement: https://goldbook.iupac.org//terms/view/D01745
- photoisomerization: https://goldbook.iupac.org//terms/view/P04622
- trans: https://goldbook.iupac.org//terms/view/C01092
- unstable: https://goldbook.iupac.org//terms/view/U06569

Source
- PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 398 (https://doi.org/10.1351/pac200779030293)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/PT07460/html
- json: https://goldbook.iupac.org/terms/view/PT07460/json
- xml: https://goldbook.iupac.org/terms/view/PT07460/xml

Citation: Citation: 'photorearrangement' 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.PT07460
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Accessed: 2026-05-18T08:36:58+00:00