反应详情

MsCl (6.61 mL, 85 mmol) was added dropwise at 0° C. to a solution of (2R,4S)-1-tert-butyl 2-methyl 4-hydroxypiperidine-1,2-dicarboxylate (21 g, 81 mmol) and DMAP (100 mg, 0.81 mmol) in pyridine (50 mL). The mixture was stirred at room temperature for 5 hours and then was concentrated under reduced pressure to remove most solvent. Brine (200 mL) was added and extracted with ethyl acetate (2×200 mL). The organic layer was dried over MgSO4, filtered and concentrated under reduced pressure to give title compound 26.7 g (98%) as colorless oil. LC-MS: 338.1 (t=1.9 min).

1. concentrationwas concentrated under reduced pressure
2. customto remove most solvent
3. additionBrine (200 mL) was added
4. extractionextracted with ethyl acetate (2×200 mL)
5. dry with materialThe organic layer was dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure