溴甲苯 、
methyl (1S,8aS)-1-methyl-3,6-dioxo-1,2,4,7,8,8a-hexahydropyrrolo[1,2-a]pyrazine-7-carboxylate 在
sodium methylate 作用下,
以
四氢呋喃 为溶剂,
生成 methyl (1S,7S,8aS)-7-benzyl-1-methyl-3,6-dioxo-2,4,8,8a-tetrahydro-1H-pyrrolo[1,2-a]pyrazine-7-carboxylate 、 methyl (1S,7R,8aS)-7-benzyl-1-methyl-3,6-dioxo-2,4,8,8a-tetrahydro-1H-pyrrolo[1,2-a]pyrazine-7-carboxylate