The γ-oxoketenes, which are accessible from methyl 1,3,4-oxadiazin-6-one-2-carboxylate-1 and cycloalkenes, are shown to undergo an intramolecular [2+2] cycloaddition either on heating or on photolysis to give different stereoisomers of β-lactones of the 3-oxo-2-oxabicyclo[2.2.0]hexane-type.
可以从1,3,4-恶二嗪-6-一-2-
羧酸酯-1和环烯烃获得的γ-氧杂
环丁烷在加热或光解过程中会发生分子内[2 + 2]环加成反应,从而生成3-氧代-2-氧杂双环[2.2.0]己烷型β-内酯的不同立体异构体。