反应详情

The mixture of tert-butyl 4-aminopiperidine-1-carboxylate hydrochloride (512 mg, 2.16 mmol), methyl 3-chloro-3-oxopropanoate (232 μL, 2.16 mmol), and DIPEA (828 μL, 4.75 mmol) in DCM (20 mL) was stirred at room temperature overnight. The solvent was removed under reduced pressure and the residue was purified by flash chromatography (eluent EtOAc) to afford tert-butyl 4-(3-methoxy-3-oxopropanamido)piperidine-1-carboxylate as a white solid (500 mg, 78%). MS (m/z): 301.1 (M+H). This material (500 mg, 1.67 mmol) was dissolved in MeOH/THF/H2O (2 mL/2 mL/1 mL), and LiOH×H2O (280 mg, 6.75 mmol) was added to the solution. The reaction mixture was stirred for 2 hrs, the solvent was removed under reduced pressure and the residue was purified by flash chromatography (eluent CH3Cl/MeOH/AcOH) to afford the title compound 42 (300 mg, 63% yield) as yellowish syrup. MS (m/z): 287.1 (M+H).

1. customThe solvent was removed under reduced pressure
2. customthe residue was purified by flash chromatography (eluent EtOAc)