反应详情

According to the method of Preparation 2, (2R)-2-[2-(tert-butoxy)-2-oxoethyl]pent-4-enoic acid (646 mg, 3.02 mmol) was reacted with (2S)-amino-N-[(1S)-2-methoxy-1-phenylethyl]-3-methylbutanamide hydrochloride (from b) above)(908 mg, 3.17 mmol) for 1 h at 4° C. and then 18 h at 20° C. The mixture was concentrated under reduced pressure, and partitioned between ethyl acetate (100 mL) and saturated aqueous sodium bicarbonate (100 mL). The layers were separated and aqueous layer extracted again with ethyl acetate (100 mL). The combined organic layers were dried (MgSO4), and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with dichloromethane:methanol 98:2) to give tert-butyl (3R)-3-({[({[(1S)-2-methoxy-1-phenylethyl]amino}carbonyl)-(1S)-2-methyl-1-propyl]amino}carbonyl)hex-5-enoate (1.08 g, 80%), as a white solid.

1. custom18 h
2. customat 20° C
3. concentrationThe mixture was concentrated under reduced pressure
4. custompartitioned between ethyl acetate (100 mL) and saturated aqueous sodium bicarbonate (100 mL)
5. customThe layers were separated
6. extractionaqueous layer extracted again with ethyl acetate (100 mL)
7. dry with materialThe combined organic layers were dried (MgSO4)
8. concentrationconcentrated under reduced pressure
9. customThe residue was purified by flash chromatography (eluting with dichloromethane:methanol 98:2)