反应详情

To a solution of ethyl 1-(propylcarbamoyl)cyclopropanecarboxylate (Example 183d) (1.65 g, 8.27 mmol) in EtOH (70 mL) was added NaBH4 (0.97 g, 25.64 mmol) at rt. The obtained mixture was stirred at rt over 2 days, quenched with 1.5M HCl and concentrated under reduced pressure. The concentrated mixture was extracted with EtOAc (4×70 mL), the combined extract was washed with saturated NaHCO3 and brine, and was dried over MgSO4. The filtrate was evaporated and the residue was purified by chromatography on silica gel using the solvent gradient hexanes→hexanes/EtOAc (1:9), to furnish 1.14 g (88%) of the product as a white solid. 1H-NMR (400 MHz, DMSO-d6) δ 7.49 (broad s, 1H), 5.09 (broad s, 1H), 3.49 (s, 2H), 3.05 (q, J=6.4 Hz, 2H), 1.41 (hex, J=7.6 Hz, 2H), 0.86-0.91 (m, 2H), 0.83 (t, J=7.2 Hz, 3H), 0.55-0.60 (m, 2H).

1. customquenched with 1.5M HCl
2. concentrationconcentrated under reduced pressure
3. extractionThe concentrated mixture was extracted with EtOAc (4×70 mL)
4. extractionthe combined extract
5. washwas washed with saturated NaHCO3 and brine
6. dry with materialwas dried over MgSO4
7. customThe filtrate was evaporated
8. customthe residue was purified by chromatography on silica gel using the solvent gradient hexanes→hexanes/EtOAc (1:9)