Farbstoffsensibilisierte Photo‐Oxygenierung von 6,6‐Dimethylfulven. Eine neue 1,2‐Dioxolan‐Umlagerung

Abstract

Abstract The dye sensitized photo‐oxygenation of 6,6‐dimethylfulvene ( 1 ) in solution at 15° gives enol lactone 2 , along with ketoles 3 and 4. The following mechanism is proposed: initially formed endoperoxide 11 undergoes a 1,2‐dioxolan rearrangement to give allen epoxide 12 , which then isomerizes to cyclopropanone 13. 13 can then cyclise to give 2 and 3 .