4-Methylmorpholine → Ammonia

Participants

Reaction Steps

N-methylmorpholine (0.085 ml) was added to a solution of (2S)-1-(1,3-benzoxazol-2-yl)-2-piperidinecarboxylic acid (95.5 mg) [see Preparation 3], hydroxybenzotriazole hydrate (89.0 mg), 2-piperidinoethylamine (50 mg) [see J. Chem. Soc, (1935), 1421-1426] and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (140 mg) in dichloromethane (20 ml). The reaction mixture was stirred at room temperature for 18 hours, after which time the mixture was diluted with water and the organic layer was separated, dried over magnesium sulphate and the solvent removed under reduced pressure. The crude product was purified by coloumn chromatography on silica gel eluting with a solvent gradient of 4:1:0, changing to 0:95:5, by volume, hexane: ethyl acetate: 0.88 aqueous ammonia solution solution to afford (2S)-1-(1,3-benzoxazol-2-yl)-N2 -(2-piperidinoethyl)-2-piperidinecarboxamide (109 mg) as a white solid.

Provenance & Evidence