Photo-oxygenation of Styrenic Estrogens: Product characterization and kinetics of the dye-sensitized photo-oxygenation of 9,11-didehydroestrone derivatives
The dye-sensitizedphoto-oxygenation of 3-hydroxyestra-1,3,5(10), 9(11)-tetraen-17-one (8) gives a complex mixture from which only the 1,4-endo-peroxide 10 can be isolated in low yield. In contrast, the 3-methoxy derivative 9 yields the C-seco-aldehyde 11 as a major product, suggesting that 1,2-dioxetane is a primary photo-oxygenation intermediate. As the electron-donating character of the substituent