General procedure for the synthesis of 4-amino-N-1-acetylpiperidine from 1-acetylpiperidin-4-one (CAS: 135581-16-7, 10 g, 70 mmol):
1. Oximization reaction: 1-acetylpiperidin-4-one was dissolved in 200 mL of ethanol, hydroxylamine hydrochloride (10 g, 143 mmol) and pyridine (10 mL) were added. The reaction mixture was heated to 70 °C and maintained for 1.5 hours. Upon completion of the reaction, the solvent was removed under reduced pressure and the residue was treated with cold water and cooled to 0 °C. The resulting slurry was filtered and dried under vacuum to give 1-acetylpiperidin-4-one oxime (6.5 g, white solid, 59% yield).
2. Hydrogenation reaction: The oxime (2.0 g, 12 mmol) prepared above was dissolved in 50 mL of ethanol, and nickel ruanne (0.2 g) was added after being washed several times with water. The mixture was transferred to a Parr reactor and hydrogenated at 50 psi hydrogen pressure for 16 hours. Upon completion of the reaction, the reaction mixture was carefully filtered and the filtrate was evaporated under reduced pressure to afford 4-amino-N-1-acetylpiperidine (1.7 g, green solid, 100% yield). The product was analyzed by GC-MS, m/z = 142.
