反应详情

Isopropyl chloroformate (1.0M in toluene, 43.4 mL, 43.4 mmol) was added dropwise to a mixture of 4-piperidinemethanol (5 g, 43.4 mmol) and triethylamine (12.1 mL, 86.8 mmol) in CH2Cl2 (150 mL) at 0° C. over 20 min. The mixture was stirred at ambient temperature overnight. The mixture was washed with water, followed by brine. The organic layer was separated and dried over MgSO4, filtered, and the filtrate was concentrated. The crude product was purified by chromatography on a silica gel column using 0 to 5% MeOH/CH2Cl2 to give 7.76 g (89%) of 1-methylethyl 4-(hydroxymethyl)-1-piperidinecarboxylate as a clear oil. 1H NMR (400 MHz, CDCl3): δ 4.93-4.78 (m, 1H), 4.19-4.09 (m, 2H), 3.47 (d, 2H, J=6.2 Hz), 2.75-2.65 (m, 2H), 1.75-1.56 (m, 3H), 1.21 (d, 6H, J=6.2 Hz), 1.17-1.06 (m, 2H); LRMS (ESI), m/z 202 (M+H).

1. washThe mixture was washed with water
2. customThe organic layer was separated
3. dry with materialdried over MgSO4
4. filtrationfiltered
5. concentrationthe filtrate was concentrated
6. customThe crude product was purified by chromatography on a silica gel column