Triethylamine → benzyl-{3-[(4R)-benzyl-2-oxo-1,3-oxazolidin-3-yl)-3-oxo-propyl]-carbamic acid phenyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred solution of 3-{benzyl[(benzyloxy)cabonyl]amino}propanoic acid (13.80 g, 44.04 mmol) and triethylamine (18.5 mL, 132.1 mmol) in anhydrous THF (220 mL) at −25° C. was slowly added pivaloyl chloride (6.03 mL, 48.44 mmol) to immediately form a white precipitate. The reaction mixture was stirred at −20° C. for 1 h, prior to the sequential addition of LiCl and (R)-(+)-4-benzyl-2-oxazolidinone. After stirring the reaction mixture at rt for 16 h, the reaction was quenched with saturated aqueous NaHCO3 (80 mL) and water (80 mL). The aqueous phase was extracted twice with ethyl acetate and the combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated under reduced pressure. The residue was purified by Combiflash (20-40% EtOAc/hexane) to give benzyl-{3-[(4R)-benzyl-2-oxo-1,3-oxazolidin-3-yl)-3-oxo-propyl]-carbamic acid phenyl ester as a colorless semi-solid (17.00 g, 82% in yield). MS (ESI): 473.1 (M+H+).

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