Benzyl chloroformate → (R)-benzyl 3-methyl-3-((R)-2-oxo-4-phenyloxazolidine-3-carbonyl)pyrrolidine-1-carboxylate

Participants

Reaction Steps

To a suspension of (R)-3-((S)-1-benzyl-3-methylpyrrolidine-3-carbonyl)-4-phenyloxazolidin-2-one (145.50 g, 399.25 mmol) and NaHCO3 (33.54 g, 399.25 mmol) in dry DCE (1000 mL) at ambient temperature was added dropwise a solution of benzylchloroformate (134.87 mL, 958.19 mmol) in DCE (100 mL) and the reaction was stirred at ambient temperature for 24 hours. The reaction was diluted with 1N HCl (500 mL) and the layers were separated. The organic layer was washed with 1M HCl (250 mL), dried (MgSO4), filtered and concentrated under reduced pressure to a thick yellow residue. The residue was purified by flash chromatography (5% ethyl acetate/DCM) to give (R)-benzyl 3-methyl-3-((R)-2-oxo-4-phenyloxazolidine-3-carbonyl)pyrrolidine-1-carboxylate (85.1 g, 208.35 mmol, 52.2% yield).

Provenance & Evidence