Direct Photolysis and Electron Transfer Photooxygenation of Enol Acetates of 3-Phenylpropiophenones

Article abstract of DOI:10.1007/BF00808680

Direct photolysis of enol acetates of 3-phenylpropiophenones 1a-c gives rise to the parent propiophenones 2a-c and the 1,3-acyl shift products 3a-c.By contrast, 2,4,6-triphenylpyrylium tetrafluoroborate sensitized photolysis of substrates 1a-c affords the α-acetyloxypropiophenones 7a-c as the most general products.These results have been rationalized according to the generation of radical pairs in the direct photolysis and radical cations in the photoinduced electron transfer processes. Keywords.Enol acetates of 3-phenylpropiophenones; 1,3-Acyl migration; Photoinduced electron transfer; 2,4,6-triphenylpyrylium tetrafluoroborate.