The photochemical behaviour of 2-alkylamino 2-cyclohexenones is very sensitive to the nitrogen substituents. α-Ketoazetidines are produced by irradiation of 2- methanesulfonamido-2-cyclohexenones; however a desulfonation and aryl migration process can compete in the case of 2-arenesulfonamido-2-cyclohexenones. Furthermore divinylamine and photo-Fries rearrangements are the main reactions with 2-anilino 2- ...