反应详情

温度

5 °C

To a cold (5° C.) solution of methyl 4-hydroxypiperidine-2-carboxylate, 13a, (5.17 g, 32.48 mmol) and triethylamine (6.00 mL, 43.05 mmol) in CH2Cl2 (135 mL) was added dropwise benzyl chloroformate (6.20 mL, 43.43 mmol) over 10 min. The resulting solution was stirred at 5° C. for 1 hour and then allowed to warm to room temperature. The reaction mixture was diluted with water and the layers were separated. The aqueous was re-extracted with CH2Cl2 and the combined organics were dried over MgSO4, filtered and evaporated to dryness. The crude was passed through a plug of silica gel, eluting with 30-80% EtOAc/Hexanes to afford the desired product, 13b.

1. temperatureto warm to room temperature
2. customthe layers were separated
3. extractionThe aqueous was re-extracted with CH2Cl2
4. dry with materialthe combined organics were dried over MgSO4
5. filtrationfiltered
6. customevaporated to dryness
7. washeluting with 30-80% EtOAc/Hexanes