73396-41-5Relevant academic research and scientific papers
ON THE PHOTOISOMERIZATION OF BICYCLODIENONES
Hart, Harold,Chen, Sun-Mao,Nitta, Makoto
, p. 3323 - 3328 (1981)
Two bicyclodienones, which differ from one another only by the presence or absence of an O atom as the "n" bridge, show very different photoisomerization behavior.Irradiation of hexamethyl-8-oxabicyclooctadienone 12 gives endo-6-acetylpentamethylbicyclohexenone 16, probably via an initial sigmatropic rearrangement (Scheme 3).In contrast, hexamethylbicycloheptadienone 14 photoisomerizes via an initial -sigmatropic rearrangement, the isolated product being the relatively stable cyclopentadiene-ketene 26.The methylene analog of 14 (i.e.32) rearranges similarly, giving allene 33 and alkyne 34.The mechanisms of these photoisomerizations are discussed.
