Hydrochloric Acid → Ethyl 3-(2,4-difluorophenyl)-3-oxopropanoate

To a solution of 2,4-difluorobenzoic acid (10 g, 63.3 mmol) in tetrahydrofuran (150 ml) was added 1,1′-carbonylbis-1H-imidazole (11.3 g, 69.6 mmol) and the mixture was stirred at room temperature for 30 min. Monoethyl malonate magnesium salt (10 g, 34.8 mmol) was added to the reaction solution and the mixture was stirred at room temperature for 2 hrs. To the reaction solution were added ethyl acetate (50 ml) and water (50 ml), and conc. hydrochloric acid was added until the aqueous layer showed acidic pH. The reaction solution was extracted with ethyl acetate (200 ml×2). The extract-was washed with saturated brine, dried-over anhydrous magnesium sulfate and evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=4:1) to give ethyl 3-(2,4-difluorophenyl)-3-oxopropionate (9.85 g, 74%) as a brown oil.

1. stirringthe mixture was stirred at room temperature for 2 hrs
2. additionwas added until the aqueous layer
3. extractionThe reaction solution was extracted with ethyl acetate (200 ml×2)
4. washThe extract-was washed with saturated brine, dried-over anhydrous magnesium sulfate
5. customevaporated under reduced pressure
6. customThe residue was purified by silica gel column chromatography (hexane:ethyl acetate=4:1)

ORDレコード

ord-27841a638ee74fe491e9cedf122e4a95

出典データセット

uspto-grants-2006_01

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06982348B2