反应详情

温度

25 °C

Under a nitrogen stream, 1-(tert-butoxycarbonyl)piperidine-3,5-dicarboxylic acid (5.00 g, 18.3 mmol) was suspended in tetrahydrofuran (10.0 mL), and trifluoroacetic anhydride (3.80 mL, 27.5 mmol) was added dropwise at 20-30° C. After completion of the dropwise addition, the mixture was stirred at 20-30° C. for 1 hr. To the reaction mixture was added dropwise heptane (20.0 mL) at 20-30° C., and the mixture was cooled to 0-10° C. and stirred for 3 hr. The precipitated crystals were collected by filtration, washed with heptane (3.00 mL), and dried under reduced pressure at 40° C. to give tert-butyl 2,4-dioxo-3-oxa-7-azabicyclo[3,3,1]nonane-7-carboxylate as a white crystalline powder (4.03 g, yield 86.1%).

1. additionAfter completion of the dropwise addition
2. temperaturethe mixture was cooled to 0-10° C.
3. stirringstirred for 3 hr
4. filtrationThe precipitated crystals were collected by filtration
5. washwashed with heptane (3.00 mL)
6. customdried under reduced pressure at 40° C.