反应详情

温度

0 °C

An ice cold solution of 2-oxo-1-pyrrolidineacetic acid (2.2 g) and triethylamine (2.15 ml) in dimethylformamide (10 ml) was treated dropwise while stirring with butyl chloroformate (1.95 ml). After stirring at 0° C. for 30 minutes, 2,2-dimethyl-4-imidazolidinone (1.75 g) was added at once, and stirring was continued at room temperature overnight. After evaporation under reduced pressure the residue was chromatographed on a silica gel column, eluting with dichloromethane/methanol 1:1. The selected fractions were collected and evaporated to give an oil which was washed twice with ethyl acetate. The residue was crystallized from ethyl acetate, to give the title compound as a white powder, m.p. 214°-217° C. (decomp.).

1. stirringstirring
2. waitwas continued at room temperature overnight
3. customAfter evaporation under reduced pressure the residue
4. customwas chromatographed on a silica gel column
5. washeluting with dichloromethane/methanol 1:1
6. customThe selected fractions were collected
7. customevaporated
8. customto give an oil which
9. washwas washed twice with ethyl acetate
10. customThe residue was crystallized from ethyl acetate