139290-70-3

6638-79-5

84358-13-4

139290-70-3

The general procedure for the preparation of 1-Boc-4-[methoxy(methyl)carbamoyl]piperidine from 1-Boc-4-piperidinecarboxylic acid (2.34 g, 10.2 mmol) and dimethylhydroxylamine hydrochloride (1.5 g, 15 mmol) in DMF (50 mL) was as follows: to a stirred 1-Boc-4-piperidinecarboxylic acid and dimethylhydroxylamine hydrochloride at room temperature in a suspension in DMF was added triethylamine (2.8 mL, 20 mmol). After stirring for 10 min, HOBt (1.62 g, 12 mmol) and EDCI (2.3 g, 12 mmol) were added sequentially. The reaction mixture was stirred overnight and subsequently concentrated. The concentrated residue was dissolved in 1N HCl (100 mL) and extracted with EtOAc (3 × 100 mL). The organic phases were combined, washed sequentially with saturated NaHCO3 solution (50 mL), brine (50 mL), dried over MgSO4 and concentrated to give a colorless oily product (2.79 g, yield >100%). The product was characterized by 1H NMR (500 MHz, CDCl3) and MS (ESI+): 1H NMR δ 4.14 (m, 2H), 3.71 (s, 3H), 3.19 (s, 3H), 2.78 (m, 3H), 1.68 (m, 4H), 1.46 (s, 9H); MS (ESI+) m/z 217.72 (M+H+- Isobutene).