F'hotochemical reactions of a-oxoamides having various substituents have been studied. Irradiation of N, N-dialkyl-a-oxoamides (Ib-d, h) in methanol yielded the corresponding oxazolidin-4-ones (2b-d, h), as main products, while that of N, N-dibenzyl-a-oxoamides (le and li) in an aprotic solvent gave the corresponding 8-lactams (3e and 3j) predominantly. N- Substituted benzoylformanilides (lk and 11) afforded type I1 elimination products on ...