反应详情

温度

220 °C

A solution of 20.3 g (0.084 mole) 3-ethoxycarbonyl-5-oxo-3-pyrrolidineacetic acid, ethyl ester [J. Org. Chem. 46, 2757 (1981)]in 40 ml of 40% aqueous methylamine was stirred at room temperature overnight, then placed in an oil bath and gradually heated to 220° C. over 30 minutes allowing volatiles to distill from the open flask. The crude product was crystallized from ethanol to afford 12.56 g of 2-methyl-2,7-diazaspiro[4.4]nonane-1,3,8-trione, mp 201°-204° C.

1. customplaced in an oil bath
2. distillationto distill from the open flask
3. customThe crude product was crystallized from ethanol