Chemoselective light-induced reactivity of ß-enaminones.

The irradiation of ß-enaminones, generated in situ from cyclic 1,3-diketones and activated alkenes leads to polyheterocyclic skeletons. The photoproduct chemoselectivity depends on the type of cyclic 1,3-diketones employed viz., 2-acetylcyclopentanone and 2-acetylcyclohexanone. The observed chemoselectivity was rationalized based on the Dieckmann-Kon rule.