Photoinduced azidohydroperoxidation of myrtenyl hydroperoxide with semiconductor particles and lucigenin as PET-catalysts

The allylic hydroperoxide 2 (myrtenyl hydroperoxide), available from singlet oxygen photooxygenation of beta-pinene (1), is converted into the azido bis-hydroperoxide 3 by an electron-transfer induced azidyl radical formation and trapping of the initial tertiary carbon radical by triplet oxygen. The azido bis-hydroperoxide 3 is reduced to the azido 1,2-diol 4 or the amino diol 5, respectively. Beside classical fluorescent PET sensitizers such as rhodamines, also nanosized semiconductor particles as well as lucigenin were applied as catalysts. The electron transfer rate of azide oxidation was determined for lucigenin by fluorescence quenching analysis.