The dye-sensitized photo-oxygenation of alkylidenecyclopropanes 1a–4a at–50° C gives the hydroperoxydes 1b–4b, which were reduced in situ by PPh3 into 1- alkenylcyclopropanols 1c–4c in high yield. At higher temperatures, 1b–4b rearranged exclusively into β′-hydroxy α-enones 1d–4d if pyridine was added (α, α′-dienones 1e–4e are also formed competitively in absence of pyridine). At 3° C the photosensitised ...
![螺[3.4]辛-1-酮结构式](https://image.chemsrc.com/caspic/418/37609-31-7.png)
