Ammonia → (S)-1-N-Boc-Piperidine-2-carboxamide

Participants

Reaction Steps

Anhydrous ammonia gas was bubbled through a solution of (S)-(−)-1-(tert-butoxycarbonyl)-2-piperidine carboxylic acid (500 mg, 2.18 mmol) in DMF (50 ml) for 15 minutes. PyBop (1.25 g, 2.40 mmol) was added. After 5 hours, solvent was evaporated under reduced pressure. A solution of the resultant residue in ethyl acetate was washed with 5% citric acid (50 ml×3), 1 N NaOH (50 ml×3), dried with MgSO4, filtered, and concentrated to give 450 mg of (S)-2-carbamoyl-piperidine-1-carboxylic acid tert-butyl ester as a clear oil in 95% yield, which was used without further purification.

Provenance & Evidence