Acetic Acid → (2R,5S)-tert-butyl 2-methyl-5-(((R)-3-methylmorpholino)methyl)piperazine-1-carboxylate

Participants

Reaction Steps

Pd/C (33 g) and acetic acid (220 mL) were added to a solution of (2R,5S)-4-benzyl-2-methyl-5-((R)-3-methyl-morpholin-4-ylmethyl)-piperazine-1-carboxylic acid tert-butyl ester (41.3 g, 102 mmol) in EtOH (300 mL). The mixture was stirred under H2 (1 atmosphere) at room temperature for 18 h. The reaction mixture was then filtered through a pad of Celilte to remove the catalyst and the solvent was removed in vacuo. The crude material was partitioned between saturated aqueous NaHCO3 and DCM and the product extracted with DCM (3×). The organic phase was dried over MgSO4, filtered and concentrated in vacuo to give the title compound (30.5 g) as a pale yellow oil. 1H NMR (CDCl3): 4.43-3.87 (1H, m), 3.78 (1H, d), 3.73-3.55 (3H, m), 3.32 (1H, dd), 3.22 (1H, dd), 3.16-2.93 (3H, m), 2.93-2.72 (1H, m), 2.55-2.35 (2H, m), 2.35-2.15 (2H, m), 1.89 (1H, dd), 1.45 (9H, s), 1.26 (3H, d), 0.96 (3H, d).

Provenance & Evidence