The sensitized photooxygenation of several 9-vinylphenanthrenes in carbon tetrachloride was investigated. In the cases of 9-vinyl-and 9-(β-substituted vinyl) phenanthrenes, the 1, 4- cycloaddition of singlet oxygen to a conjugated system composed of the side chain and 9, 10-double bond of the ring surpassed other oxidation modes, ie, the “ene” reaction and 1, 2- cycloaddition of singlet oxygen, to give the 1, 2-dioxatriphenylene-type peroxides. On the ...
