Direct photolysis and electron transfer photooxygenation of enol acetates of 3-phenylpropiophenones
摘要:
Direct photolysis of enol acetates of 3-phenylpropiophenones la-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 la-c affords the alpha-acetyloxypropiophenones 79-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.