Cyclopentane 6-halo-1-alkene

Pandey and colleagues reported the intramolecular photocycliza-tion of 6-halo terminal alkenes using organosilicon compounds having Si-Se bond as shown in Scheme 13." The 1,5-dimethoxy-naphthalene-sensitized photoreaction generates RjSi and PhSe" by the dissociation of the radical anion of PhSe-SiRj. Key intermediates in this complex system are RjSi and PhSe. The former radical abstracts a halogen atom and the latter radical is trapped by a terminal radical giving a cyclopentane derivative. 

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