Ethyl chloroformate → HCID 57758644, compound

To a solution of (4S)-4-fluoromethyl-1-[(1R)-1-phenylethyl]-2-pyrrolidone (7.59 g, 34.3 mmol) and ethyl chloroformate (3.92 mL, 41.2 mmol) in tetrahydrofuran (150 mL), lithium bistrimethylsilyl amide (75.5 mL, 75.5 mmol, 1.0M solution in tetrahydrofuran) was added at 0° C., and the mixture was stirred the same temperature for 20 minutes. Saturated aqueous solution of ammonium chloride (200 mL) was added to the reaction mixture at the same temperature, and the mixture was extracted with ethyl acetate (200 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, and the residue was purified by silica gel column chromatography (elusion by hexane:ethyl acetate, 5:1→2:3) to obtain 8.50 g (85%) of the title compound as a pale yellow oily substance.

1. extractionthe mixture was extracted with ethyl acetate (200 mL×2)
2. washThe organic layer was washed with saturated aqueous solution of sodium chloride (100 mL)
3. dry with materialdried with anhydrous sodium sulfate
4. filtrationAfter filtration
5. concentrationthe filtrate was concentrated under reduced pressure
6. customthe residue was purified by silica gel column chromatography (elusion by hexane:ethyl acetate, 5:1→2:3)

ORD record

ord-666b6fd7c9854f608c82ddbc9c7e703b

Source dataset

uspto-grants-2009_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07563805B2