Term: Norrish–Yang reaction
https://doi.org/10.1351/goldbook.NT07427

Definition:
Photochemical process leading to the formation of cyclobutanols from excited carbonyl compounds by intramolecular γ-hydrogen abstraction (Norrish Type II photoreaction) and subsequent 1,4-diradical combination. NT07427.png

Related Terms:
1) carbonyl compounds (http://doi.org/10.1351/goldbook.C00844).
2) intramolecular (http://doi.org/10.1351/goldbook.I03130).
3) abstraction (http://doi.org/10.1351/goldbook.A00045).
4) norrish type ii photoreaction (http://doi.org/10.1351/goldbook.N04218).

Image: Not defined (https://goldbook.iupac.org/img/inline/NT07427.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–Yang 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.NT07427

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