反应详情

温度

85 °C

Ethyl N-[(1S,2S)-2-aminocyclopentyl]glycinate (HCl salt) (708 mg, 3.18 mmol) was dissolved in ethanol (16 mL), and triethylamine (4.43 mL, 31.8 mmol) was added. The resulting mixture was stirred and heated at 85° C. for 24 hours. The mixture was then cooled and concentrated under reduced pressure. Ethyl acetate was added to the residue, and the resulting slurry was filtered. The filtrate was concentrated under reduced pressure to afford (4aS,7aS)-octahydro-2H-cyclopenta[b]pyrazin-2-one, which was used without further purification. 1H NMR (500 MHz, CDCl3) δ 6.31 (s, 1H), 3.68-3.67 (m, 2H), 3.23-3.17 (m, 1H), 2.86-2.81 (m, 1H), 1.97-1.82 (m, 5H), 1.49-1.40 (m, 2H).

1. temperatureThe mixture was then cooled
2. concentrationconcentrated under reduced pressure
3. additionEthyl acetate was added to the residue
4. filtrationthe resulting slurry was filtered
5. concentrationThe filtrate was concentrated under reduced pressure