Term: Norrish Type II photoreaction
https://doi.org/10.1351/goldbook.N04218

Definition:
intramolecular abstraction of a γ-hydrogen by an excited carbonyl compound to produce a 1,4-diradical as a primary photoproduct.

Note: An example is: N04218.png

Related Terms:
1) intramolecular (http://doi.org/10.1351/goldbook.I03130).
2) abstraction (http://doi.org/10.1351/goldbook.A00045).

Image: Norrish Type II photoreaction (https://goldbook.iupac.org/img/inline/N04218.png) 

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 375 (https://doi.org/10.1351/pac200779030293)

Citation: 'Norrish Type II photoreaction' 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.N04218

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