反应详情

温度

80 °C

A mixture of powdered potassium carbonate (14.0 g, 96.2 mmol, 5 equiv.), ethyl-4-aminobutyrate (IVb) (6.5 g, 38.6 mmol, 2 equiv.) and methanesulfonic acid (R)-1-carbamoyl-propyl ester (IIi) (3.5 g, 19.3 mmol, 1 equiv.) in acetonitrile (40 ml, 11 vol.) is heated to 80° C. for 17 hours. The mixture is then filtered and the cake rinsed with acetonitrile (30 ml). Combined filtrates are concentrated to dryness under reduced pressure. The crude methyl-(S)-4-(1-carbamoylpropylamino)butyrate (VIg) obtained as a yellow oil is used directly in the next step.

1. filtrationThe mixture is then filtered
2. washthe cake rinsed with acetonitrile (30 ml)
3. concentrationCombined filtrates are concentrated to dryness under reduced pressure