Diethyl Carbonate → Ethyl 5-bromo-β-oxo-2-thiophenepropanoate

Temperature

56 °C

To a solution of 1-(5-bromothiophen-2-yl)ethanone (4.10 g, 19.99 mmol) and Diethyl carbonate (30 mL, 248 mmol) in THF (40 ml) at room temperature was added sodium hydride (1.679 g, 42.0 mmol). The resulting off-white slurry solution was gradually warmed to 56° C., and became dark brown clear solution. The reaction mixture was heated at 56° C. for 1.5 hour. The reaction mixture was poured into ice-HOAc—H2O, and extracted with ethyl acetate. The organic phase was washed (brine), dried (MgSO4) and concentrated to give a brown liquid. The crude product was purified via flash chromatography (silica gel cartridge with eluent of 0-5% ethyl acetate/hexane) to afford ethyl 3-(5-bromothiophen-2-yl)-3-oxopropanoate as an amble liquid, 4.713 g (85%). HPLC: Rt 2.856 min.

1. temperatureThe reaction mixture was heated at 56° C. for 1.5 hour
2. extractionextracted with ethyl acetate
3. washThe organic phase was washed (brine)
4. dry with materialdried (MgSO4)
5. concentrationconcentrated
6. customto give a brown liquid
7. customThe crude product was purified via flash chromatography (silica gel cartridge with eluent of 0-5% ethyl acetate/hexane)

ORD record

ord-ecc63ced10454f2ab12e822db41c6934

Source dataset

uspto-grants-2012_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08106046B2