Photochemistry of Conjugated Nitrogen–Carbonyl Systems. III. Photosensitized Oxygenation of 3- and 6-Substituted 2-Pyridones

Abstract

Irradiation of solutions of 3- and 6-substituted 2-pyridones (1) in the presence of methylene blue as a sensitizer under an oxygen atmosphere gave 3-substituted pyridine-2, 6-(lH, 3H)-diones (2) and 6-substituted pyridine-2, 3-(lH, 6H)-diones (3), respectively, which are probably derived from the intermediate endoperoxides (6). © 1987, The Pharmaceutical Society of Japan. All rights reserved.