反应详情

t-Butyl-piperidin-4-ylcarbamate (3 g, 15 mmol) obtained in Preparation Example 2-ii was dissolved in methanol (30 ml) in a 100 ml vessel, and acetone (7.70 ml, 105 mmol) and acetic acid (0.45 ml, 7.5 mmol) were added thereto while stirring. To the resulting mixture, NaCNBH3 (1.88 mg, 30 mmol) was added dropwise in 4-divided portions and reacted for 18 hrs. After the completion of reaction, ice water was poured to the reaction product while stirring, and the resulting mixture was extracted with ethyl acetate. The organic layer was separated, washed with an aqueous sodium bicarbonate solution and brine in order, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue thus obtained was subjected to a silica gel column chromatography to obtain 2.644 g of the title compound as a white solid (yield 73.3%).

1. customreacted for 18 hrs
2. additionwas poured to the reaction product
3. stirringwhile stirring
4. extractionthe resulting mixture was extracted with ethyl acetate
5. customThe organic layer was separated
6. washwashed with an aqueous sodium bicarbonate solution and brine in order
7. dry with materialdried over anhydrous sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe residue thus obtained