Borane → HCID 57758664, compound

Participants

Reaction Steps

To a solution of tert-butyl (3S)-4-hydroxy-3-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate (5.13 g, 16.1 mmol) in tetrahydrofuran (100 mL), 1.17M solution of borane in tetrahydrofuran (45.3 mL, 53.1 mmol) was added in an ice bath, and the mixture was stirred at room temperature for 13 hours. After concentrating the reaction mixture under reduced pressure, water (10 mL), ethanol (100 mL), and triethylamine (5 mL) were added to the concentrate, and the mixture was heated under reflux in an oil bath at 90° C. for 2 hours. The reaction mixture was concentrated under reduced pressure, and water (200 mL) was added to the concentrate. The mixture was extracted with ethyl acetate (200 mL×2). The resulting organic layer was washed with saturated aqueous solution of sodium chloride (200 mL), and dried with anhydrous sodium sulfate. After the filtration, the filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (hexane:ethyl acetate, 3:1→1:2) to obtain 1.50 g (31%) of the title compound as a colorless oily substance.

Provenance & Evidence