Norrish reaction
E557614
Norrish reaction subtype
intramolecular hydrogen abstraction reaction
organic chemistry reaction
photochemical cleavage reaction
photochemical reaction
The Norrish reaction is a photochemical process in organic chemistry involving the cleavage and rearrangement of carbonyl compounds under ultraviolet light, fundamental to understanding photodegradation and radical mechanisms.
Observed surface forms (2)
| Surface form | Occurrences |
|---|---|
| Norrish type II reaction | 1 |
| Norrish type I reaction | 0 |
Statements (45)
| Predicate | Object |
|---|---|
| instanceOf |
Norrish reaction subtype
ⓘ
intramolecular hydrogen abstraction reaction ⓘ organic chemistry reaction ⓘ photochemical cleavage reaction ⓘ photochemical reaction ⓘ |
| alsoKnownAs | alpha-cleavage reaction ⓘ |
| canLeadTo |
chain scission in polymers
ⓘ
fragmentation of organic molecules ⓘ |
| category |
photodegradation process
ⓘ
radical reaction ⓘ |
| field |
organic chemistry
ⓘ
photochemistry ⓘ |
| hasHistoricalSignificance | contributed to development of modern photochemistry ⓘ |
| hasType |
Norrish type I reaction
ⓘ
Norrish type II reaction ⓘ |
| importantFor |
photostability analysis of organic materials
ⓘ
radical mechanism studies ⓘ understanding photodegradation of ketones ⓘ understanding photodegradation of polymers ⓘ |
| initiatedBy | ultraviolet irradiation ⓘ |
| involves |
1,4-biradical intermediate
ⓘ
C–C bond cleavage adjacent to carbonyl group ⓘ alpha-cleavage of carbonyl compounds ⓘ carbonyl compounds ⓘ excited triplet state ⓘ gamma-hydrogen abstraction ⓘ homolytic bond cleavage ⓘ intramolecular hydrogen transfer ⓘ radical intermediates ⓘ ultraviolet light ⓘ |
| mechanism |
excitation to singlet or triplet state followed by alpha-cleavage
ⓘ
photoexcitation followed by gamma-hydrogen abstraction and beta-scission or cyclization ⓘ |
| namedAfter | Ronald George Wreyford Norrish NERFINISHED ⓘ |
| occursIn |
solid phase
ⓘ
solution phase ⓘ |
| produces |
acyl radical
ⓘ
alkene ⓘ alkyl radical ⓘ cyclobutanol derivatives ⓘ enol ⓘ |
| relatedTo |
Paternò–Büchi reaction
NERFINISHED
ⓘ
photo-Fries rearrangement NERFINISHED ⓘ |
| requires |
carbonyl chromophore
ⓘ
light of appropriate wavelength ⓘ |
| studiedIn | physical organic chemistry ⓘ |
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Norrish type II reaction