79574-61-1

79574-70-2

The general procedure for synthesizing 3-acetyl-2-fluoropyridine from 1-(2-fluoropyridin-3-yl)ethanol was as follows: referring to Example 32, 1-(2-fluoropyridin-3-yl)ethanol (39.9 g) was dissolved in dimethyl sulfoxide (200 mL) and cooled in an ice bath. A suspension of sulfur trioxide pyridine complex (90.0 g) in dimethyl sulfoxide (200 mL) was slowly added dropwise at the same temperature and triethylamine (200 mL) was added. The reaction mixture was gradually warmed to room temperature and stirred at that temperature for 20 hours. Upon completion of the reaction, water was added to the mixture and extracted with ethyl acetate. The organic phases were combined, dried with anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane-ethyl acetate=1:2) to afford the red oily product 3-acetyl-2-fluoropyridine (33.8 g, 86% yield).1H-NMR (CDCl3) δ: 2.69 (3H, dd, J=4.9,1.1 Hz), 7.34 (1H, ddd, J=7.6,4.9,2.3 Hz ), 8.34 (1H, dddd, J=9.5,7.6,2.3,1.1Hz), 8.40 (1H, dddd, J=4.9,2.3,1.1Hz).