反应详情

tert-Butyl 4-{1-[(benzoyloxy)carbonyl]piperidin-4-yl}-3-oxopiperazin-1-carboxylate (0.42 g) obtained in Example 12b) was dissolved in trifluoroacetic acid (1 mL) and dichloromethane (1 mL), and the mixture was stirred at room temperature for one hour. The reaction mixture was concentrated, toluene was added to the residue and it was concentrated again under reduced pressure. The residue was dissolved in dichloromethane (15 mL) and formalin (37%; 0.5 mL) was added. After the reaction mixture was stirred at room temperature for 2 hours, sodium triacetoxyborohydride (0.53 g) was added, and the mixture was stirred at room temperature for 15 hours. The reaction mixture was washed with an aqueous sodium bicarbonate solution and dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to obtain the title compound (0.38 g, quantitative) as a light yellow oil.

1. concentrationThe reaction mixture was concentrated
2. additiontoluene was added to the residue and it
3. concentrationwas concentrated again under reduced pressure
4. dissolutionThe residue was dissolved in dichloromethane (15 mL)
5. additionformalin (37%; 0.5 mL) was added
6. additionsodium triacetoxyborohydride (0.53 g) was added
7. stirringthe mixture was stirred at room temperature for 15 hours
8. washThe reaction mixture was washed with an aqueous sodium bicarbonate solution
9. dry with materialdried over anhydrous sodium sulfate
10. distillationthe solvent was distilled off under reduced pressure