反应详情

KOH (3.87 g, 69.0 mmol) in water (50 mL) was added to ethyl 2-cyclopentyl-2-(methoxycarbonylamino)acetate (Compound I2.1) (7.6 g, 33.2 mmol) in ethanol (20 mL). The resultant mixture was stirred at rt for 5 h. Part of the solvent was removed under reduce pressure. The remaining mixture was extracted with Et2O (2×50 mL). The pH of the water layer was acidified by additions of HCl (1N, 20 mL) and the resultant mixture was extracted with DCM (3×50 mL), dried (MgSO4) and concentrated under reduce pressure. The residue was purified via Biotage (gradient: 10-80% of DCM/MeOH/HOAc (1: 0.05: 0.01) in DCM, KP-SIL 340 g column), KP-SIL 340 g column) to give the title product (5.95 g, 85%). 1H NMR (600 MHz, CDCl3) 1.26-1.48, 1.49-1.68, 1.68-1.85, 2.28, 3.69, 4.31, 5.12. Total no of protons: 14.

1. customPart of the solvent was removed
2. extractionThe remaining mixture was extracted with Et2O (2×50 mL)
3. extractionthe resultant mixture was extracted with DCM (3×50 mL)
4. dry with materialdried (MgSO4)
5. concentrationconcentrated
6. customThe residue was purified via Biotage (gradient: 10-80% of DCM/MeOH/HOAc (1: 0.05: 0.01) in DCM, KP-SIL 340 g column), KP-SIL 340 g column)