tert-Butyl(3R)-3-fluoromethyl-4-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate → (3R)-3-Fluoromethyl-4-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylic acid

Participants

Reaction Steps

To a solution of tert-butyl (3R)-3-fluoromethyl-4-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate (910 mg, 2.71 mmol) in dichloromethane (9 mL), trifluoroacetic acid (9 mL) was added dropwise in an ice bath, and the mixture was stirred at room temperature for 3 hours. After concentrating the reaction mixture under reduced pressure, saturated aqueous solution of sodium hydrogencarbonate (20 mL) was added to the concentrate in an ice bath, and the aqueous solution was washed with diethylether (50 mL). To the aqueous layer was added 1 mol/l hydrochloric acid to pH 2 to 3 in an ice bath, and the solution was extracted with chloroform (100 mL×2). The organic layer was washed with saturated aqueous solution of sodium chloride (100 mL), and dried with anhydrous sodium sulfate. After filtration, the filtrate was concentrated under reduced pressure. The concentrate was azeotropically distilled by adding toluene (20 mL), and dried under reduced pressure to obtain 910 mg (quantitative) of the title compound as a white solid.

Provenance & Evidence