反应详情

温度

0 °C

At −30° C. and under N2 atmosphere, to a solution of ethyl 4-oxopiperidine-1-carboxylate (282) (6.0 g, 35.1 mmol) in anhydrous Et2O (100 mL) was added MeMgBr (3.0 M, 14 mL, 42.1 mmol). The resulting mixture was stirred at 0° C. for 2 hours before being quenched with aqueous NH4Cl solution. The mixture was extracted with DCM (30 mL×3). The combined organic layers were washed with brine, dried over Na2SO4, concentrated in vacuo and subjected to silica flash column chromatography using 0 to 50% EtOAc in PE (petroleum ether) to isolate ethyl 4-hydroxy-4-methylpiperidine-1-carboxylate (283) (4 g, 61%) as an oil.

1. custombefore being quenched with aqueous NH4Cl solution
2. extractionThe mixture was extracted with DCM (30 mL×3)
3. washThe combined organic layers were washed with brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated in vacuo