Hydrochloric Acid → 4-Acetyl-piperidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of tert-butyl 4-(methoxy(methyl)carbamoyl)piperidine-1-carboxylate (4.0 g, 14.69 mmol) in tetrahydrofuran (50 mL) was added methylmagnesium bromide solution (5.25 g, 44.06 mmol, 3M) at −70° C. over 0.5 hour. The resultant mixture was stirred at room temperature for 6 hours. The reaction solution was adjusted pH to 6.0 by 1.0M hydrochloride solution. The aqueous phase was extracted with ethyl acetate (100 ml*3). The combined organic layers was washed with brine, dried over sodium sulfate and concentrated under vacuum to give tert-butyl 4-acetylpiperidine-1-carboxylate as a yellow liquid (2.6 g, yield 77.8%). LRMS (M+H+) m/z: calcd 227.15. found 228.

Provenance & Evidence