Irradiation of pyridazin-3-one 1-ethoxycarbonylimide (9a) resulted in ring contraction to give the azamaleimide (11), whereas the 6-methyl derivative (9b), upon irradiation, afforded the 3-pyrrolin-2-one (12). On the other hand, the photolysis of 2-methylpyridazin-3-one 1-imides (10a, b) gave both azamaleimides (13a, b) and 3-pyrrolin-2-ones (14a, b). The mechanism of this photoinduced ring contraction reaction is discussed.
对
吡嗪-3-酮 1-乙氧基碳
酰亚胺(9a)的辐射处理导致环收缩,生成了氮杂马来
酰亚胺(11),而6-甲基衍
生物(9b)在辐射后则获得了3-
吡咯烯-2-酮(12)。另一方面,
2-甲基吡嗪-3-酮 1-
亚胺(10a, b)的光解反应生成了氮杂马来
酰亚胺(13a, b)和3-
吡咯烯-2-酮(14a, b)。讨论了这种光诱导环收缩反应的机制。