Ammonium Hydroxide → tert-Butyl 4-carbamoyl-4-methylpiperidine-1-carboxylate

Temperature

60 °C

To a solution of 1-(tert-butoxycarbonyl)-4-methylpiperidine-4-carboxylic acid (2.85 g, 11.7 mmol) in DMF (57 mL) was added CDI (2.28 g, 14.1 mmol). The mixture was stirred at 60° C. for 30 minutes, then cooled to room temperature. Ammonium hydroxide (18.2 mL, 117 mmol) was added cautiously and stirring continued for 1 hour. The mixture was then evaporated to give a colourless oil. It was extracted with ethyl acetate and the organic layer washed with HCl (1 M), with water, sodium hydrogen carbonate solution, brine, dried over sodium sulfate, filtered and evaporated. The residue was taken up in toluene, then hexane was added and the mixture was stirred at room temperature for 15 minutes. The precipitate was filtered, washed with hexane and dried to give the title compound (2.55 g, 90%) as a white solid.

1. temperaturecooled to room temperature
2. stirringstirring
3. waitcontinued for 1 hour
4. customThe mixture was then evaporated
5. customto give a colourless oil
6. extractionIt was extracted with ethyl acetate
7. washthe organic layer washed with HCl (1 M), with water, sodium hydrogen carbonate solution, brine
8. dry with materialdried over sodium sulfate
9. filtrationfiltered
10. customevaporated
11. additionhexane was added
12. stirringthe mixture was stirred at room temperature for 15 minutes
13. filtrationThe precipitate was filtered
14. washwashed with hexane
15. customdried

ORD record

ord-b70548b3c797467ea36539418e082941

Source dataset

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08486967B2