Recent Mechanistic Insights in the Singlet Oxygen Ene Reaction

Singlet oxygen reacts with alkenes, which bear allylic hydrogens, in an ene fashion to afford allylic hydroperoxides. This reaction, apart from its synthetic usefulness, has received extensive mechanistic attention. Numerous experimental studies (e.g., trapping of intermediates, deuterium kinetic isotope effects, regio- or stereoselectivity studies etc.) and to a lesser extend computational work, support a stepwise mechanism with the formation of a three-membered ring (perepoxide-like) intermediate. This Account mainly highlights our group's earlier and recent experimental efforts to ascertain facts relating to this concept.