反应详情

A stirred solution of ethyl 3-oxo-3-(2,3,4,5-tetrafluorophenyl)propionate (20.3 g, 76.8 mmol), Ac2O (44.0 mL, 0.465 mol) and triethyl orthoformate (25.6 mL, 0.154 mol) was heated at 120° C. for 3 hours. The mixture was concentrated in vacuo and dried under high vacuum. 1-amino-1-(2-hydroxyethyl)cyclopentane (9.94 g, 76.9 mmol) in anhydrous toluene (50 mL) was slowly added to a solution of the mixture in anhydrous toluene (200 mL) at 0° C. The resulting mixture was stirred at room temperature for 2 hours. The solvent was removed by evaporation. Flash chromatography (AcOEt:Hexane=2:1) of the residue gave the title compound as a colorless solid (23.2 g, 75%). 1H-NMR (400 MHz, CDCl3) δ 0.96 (0.6H, t, J=7.3 Hz), 1.09 (2.4H, t, J=7.3 Hz), 1.48-1.54 (1H, m), 1.74-1.90 (6H, m), 1.97-2.06 (4H, m), 3.78-3.85 (2H, m), 3.98-4.10 (2H, m), 6.95-7.12 (1H, m), 8.17-8.24 (1H, m), 9.81-9.94 (0.3H, m), 11.20-11.35 (0.7H, m).

1. concentrationThe mixture was concentrated in vacuo
2. customdried under high vacuum
3. customThe solvent was removed by evaporation