ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Photochemistry of Conjugated δ-Keto-enones and β,γ,δ,∊-Unsaturated KetonesOn 1π,π*-excitation the δ-keto-enones 5-8 are isomerized to compounds B (18, 22, 26, 28) via 1,3-acyl shift and to compounds C (19, 23, 27, 29) via 1,2-acyl shift, whereas the β,γ,δ,∊-unsaturated ketone 9 gives the isomers 32 and 33 by 1,2-and 1,5-acyl shift, respectively. Furthermore, isomerization of 6 to 24, dimerization of 8 to 30 and addition of methanol to 8 (8 → 31) is observed. Unlike 7 and 8 the acyclic ketones 5, 6 and 9 undergo photodecarbonylation on 1π,π*-excitation (5 → 20, 21; 6 → 20, 25; (E)-9 → 35-38).Evidence is given, that the conversion to B as well as the photodecarbonylation of 5,6 and 9 arise from an excited singulet state, but the conversion to C as well as the dimerization of 8 from the T1-state.
Additional Material:
3 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19800630620
