Dimethylacetamide → 1-(5-Fluoropyridin-2-yl)ethan-1-one

Participants

Reaction Conditions

Reaction Steps

sec-BuLi (1.9 mL, 1.4 M in hexane) was added drop wise to a solution of 2-bromo-5-fluoropyridine (500 mg, 2.8 mmol) in dry Et2O (6 mL) at −78° C. Stirring was continued at this temperature for 10 minutes, after which a solution of N,N-dimethylacetamide (290 μL, 3.1 mmol) in dry Et2O (1 mL) was added drop wise. Stirring was continued at −78° C. for 1 h, where after the reaction mixture was allowed to slowly reach rt. The reaction mixture was again cooled to −78° C. and was quenched by adding 1M HCl aq. solution (6 mL) before it was left to warm to rt over night. The water and organic phases were separated and the water phase extracted with Et2O (2×10 mL). Combined organics were washed with water and brine and dried (MgSO4). After filtration and Careful! evaporation (the title compound is volatile) the red/brown oily crude was dissolved in CH2Cl2 and a small amount of SiO2 was added. The suspension was filtered through a pad of Celite and the solvent was removed by evaporation to give the title compound (203 mg, 1.5 mmol, 52%) as an orange oil. The product was considered to be pure enough to be used directly in the next step without prior purification.

Provenance & Evidence