反应详情

To a solution of 4,4-difluoropiperidin hydrochloride (2.15 g, 14 mmol) in 30 mL of dichloromethane was added triethylamine (5.7 ml, 41 mmol), followed by 4-nitrophenyl chloroformate 40 (3.0 g, 15 mmol). After 1 h, the reaction was diluted with ethyl acetate and was washed with 3×30 mL of sat. NaHCO3, and 1×30 mL brine. The organic layer was dried over MgSO4, filtered, and concentrated to afford 4-nitrophenyl 4,4-difluoropiperidin-1-carboxylate 41 (3.9 g, 100% yield). 1H-NMR (400 MHz, CDCl3): δ 8.26 (m, 2H), 7.30 (m, 2H), 3.76 (m, 4H), 2.09 (m, 4H). MS 286.1 (calc'd) 287.1 (M+H, found).

1. washwas washed with 3×30 mL of sat. NaHCO3, and 1×30 mL brine
2. dry with materialThe organic layer was dried over MgSO4
3. filtrationfiltered
4. concentrationconcentrated