N-Methoxy-N-methylpropionamide → HCID 22473990, compound

Temperature

-70 °C

A solution of 3-bromo-4-fluorobenzo[b]thiophene (3.0 g) in tetrahydrofuran (10 ml) was added dropwise under nitrogen at −60-−70° C. over 10 minutes to a stirred solution of n-butyllithium (2.5M solution in hexanes; 6.75 ml) in ether (30 ml), then the mixture was stirred at −70° C. for 30 minutes. A solution of N-methoxy-N-methylpropionamide (1.31 g) in tetrahydrofuran (10 ml) was added dropwise at −70° C. over 10 minutes, then the mixture was stirred at −70° C. for 5 hours and allowed to stand at ambient temperature for 12 hours. The mixture was quenched by the addition of saturated aqueous ammonium chloride solution (40 ml), then the organic layer was separated, washed with saturated aqueous sodium chloride solution (40 ml), dried (MgSO4) and the solvents were removed in vacuo. The residue was purified by flash chromatography over silica using a 10:1 mixture of petroleum ether (b.p. 60-80° C.) and ethyl acetate as eluant. Appropriate fractions were combined and the solvents removed in vacuo to give 1-(4-fluorobenzo[b]thiophen-2-yl)propan-1-one (0.54 g) as a colourless solid which was used without further purification.

1. stirringthe mixture was stirred at −70° C. for 5 hours
2. waitto stand at ambient temperature for 12 hours
3. customThe mixture was quenched by the addition of saturated aqueous ammonium chloride solution (40 ml)
4. customthe organic layer was separated
5. washwashed with saturated aqueous sodium chloride solution (40 ml)
6. dry with materialdried (MgSO4)
7. customthe solvents were removed in vacuo
8. customThe residue was purified by flash chromatography over silica using
9. additiona 10:1 mixture of petroleum ether (b.p. 60-80° C.) and ethyl acetate as eluant
10. customthe solvents removed in vacuo

ORD record

ord-7681e0d42bba4105aafa007959b5415d

Source dataset

uspto-grants-2005_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06900216B2