ethyl 1-benzyl-7a-methoxy-2,5-dioxo-2,3,3a,4,5,7a-hexahydro-1H-indole-3-carboxylate 、 alkaline earth salt of/the/ methylsulfuric acid 在
potassium carbonate 作用下,
以
四氢呋喃 为溶剂,
以51.3%的产率得到ethyl 3-(2-(1,3-dioxolan-2-yl)ethyl)-benzyl-5-hydroxy-2-oxoindole-3-carboxylate