反应详情

温度

-40 °C

NaBH4 (36 g, 1.0 mol) was added in portions to a −40° C. solution of (S)-1-tert-butyl 2-ethyl 5-oxopiperidine-1,2-dicarboxylate (250 g, 0.92 mol) in EtOH (1500 mL). The reaction mixture was then stirred at −40° C. for 0.5 hr then quenched with 10% HOAc solution. After diluting with water, the mixture was extracted with DCM (3×). The combined organic layer was concentrated under reduced pressure and purified by silica gel column chromatography (1:1 petroleum ether/EtOAc) to afford (2S,5S)-1-tert-butyl 2-ethyl 5-hydroxypiperidine-1,2-dicarboxylate (205 g, 80%) as a yellow oil.

1. customthen quenched with 10% HOAc solution
2. additionAfter diluting with water
3. extractionthe mixture was extracted with DCM (3×)
4. concentrationThe combined organic layer was concentrated under reduced pressure
5. custompurified by silica gel column chromatography (1:1 petroleum ether/EtOAc)