反应详情

Lithium bis(trimethylsilyl)amide (12.9 mL, 12.9 mmol, 1M solution in THF) at −78° C. was added to 1-benzyl 3-ethyl piperidine-1,3-dicarboxylate (3.0 g, 10.3 mmol) in THF (20 mL), and the reaction was stirred at this temperature for 20 minutes. MeI (0.867 mL, 13.9 mmol) was added, and the reaction was warmed to room temperature. After 2 hours at room temperature, the mixture was poured onto saturated ammonium chloride (20 mL) and extracted with ether, washed with brine and dried over sodium sulfate. After removal of the solvent, the residue was purified by chromatography on silica gel (hexane:ethyl acetate, 5:1) to give 1-benzyl 3-ethyl 3-methylpiperidine-1,3-dicarboxylate (3.1 g, 98% yield) as an oil.

1. waitAfter 2 hours at room temperature
2. extractionextracted with ether
3. washwashed with brine
4. dry with materialdried over sodium sulfate
5. customAfter removal of the solvent
6. customthe residue was purified by chromatography on silica gel (hexane:ethyl acetate, 5:1)