Ethyl bromoacetate → Ethyl(3-ethyl-1-(4-methoxybenzyl)-2-oxopyrrolidin-3-yl)acetate

Temperature

0 °C

To a solution of diisopropylamine (3.4 mL) in tetrahydrofuran (10 mL) was added dropwise n-butyllithium (1.6 M hexane solution, 15 mL) at −78° C. under nitrogen atmosphere, and the mixture was warmed to 0° C., and stirred for 30 min. The reaction mixture was cooled to −78° C., a solution of 3-ethyl-1-(4-methoxybenzyl)pyrrolidin-2-one (2.8 g) obtained in Step B in tetrahydrofuran (10 mL) was added thereto, and the mixture was stirred at the same temperature for 1 hr. Ethyl bromoacetate (4.0 mL) was added thereto, and the mixture was stirred overnight while it was allowed to be warmed. To the reaction mixture was added saturated aqueous ammonium chloride solution, and the mixture was extracted with ethyl acetate. The obtained organic layer was washed with saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate) to give the title compound (1.5 g).

1. temperatureThe reaction mixture was cooled to −78° C.
2. stirringthe mixture was stirred at the same temperature for 1 hr
3. stirringthe mixture was stirred overnight while it
4. temperatureto be warmed
5. extractionthe mixture was extracted with ethyl acetate
6. washThe obtained organic layer was washed with saturated brine
7. dry with materialdried over anhydrous magnesium sulfate
8. customthe solvent was evaporated under reduced pressure
9. customThe residue was purified by silica gel column chromatography (hexane/ethyl acetate)

ORD record

ord-06bcd36995a545efaef946f59634834a

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09187453B2