Methyl iodide → 1-Benzyl 3-ethyl 3-methyl-4-oxopyrrolidine-1,3-dicarboxylate

Temperature

45 °C

To a solution of ethyl 1-benzyloxycarbonyl-4-oxopyrrolidine-3-carboxylate (1.0 g, 3.4 mmol) in acetone (30 mL), potassium carbonate (0.95 g, 6.9 mmol) and methyl iodide (1 mL) were added, and the mixture was stirred at 45° C. for 1 hour. The reaction mixture was concentrated under reduced pressure, and water (20 mL) was added to the concentrate. The mixture was extracted with ethyl acetate (20 mL×3). The extract was washed with 10% aqueous solution of sodium thiosulfate (20 mL) and saturated aqueous solution of sodium chloride (20 mL) in this order, 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, 4:1) to obtain 1.0 g (95%) of the title compound as a pale yellow oily product.

1. concentrationThe reaction mixture was concentrated under reduced pressure, and water (20 mL)
2. additionwas added to the concentrate
3. extractionThe mixture was extracted with ethyl acetate (20 mL×3)
4. washThe extract was washed with 10% aqueous solution of sodium thiosulfate (20 mL) and saturated aqueous solution of sodium chloride (20 mL) in this order
5. dry with materialdried with anhydrous sodium sulfate
6. filtrationAfter the filtration
7. concentrationthe filtrate was concentrated under reduced pressure
8. customthe residue was purified by silica gel column chromatography (hexane:ethyl acetate, 4:1)

ORD record

ord-91e41805dad3428f8de62edfe026e919

Source dataset

uspto-grants-2009_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07563805B2