Hydrochloric Acid → 1-(5-Fluoropyridin-2-yl)ethan-1-one

2-Bromo-5-fluoropyridine (13.0 g, 73.9 mmol), copper(I) iodide (2.10 g, 11.1 mmol) and dichlorobis (triphenylphosphine) palladium(II) in anhydrous acetonitrile (100 ml) was added tributyl(1-ethoxyvinyl)atannane (27.5 ml, 81.3 mmol). The reaction was heated at reflux. After heating for 70 hours, 1.5 M aqueous HCl (20 ml) was added to quench the reaction and the mixture was heated at reflux for 1 hour. After cooling to room temperature, the reaction mixture was neutralized with saturated sodium bicarbonate and extracted with ether (3×100 ml). The combined organic layers were dried over dried over sodium sulfate, and concentrated. After removal of solvent, the resulted residue was purified by column chromatography (hexane-ether=5:1) to give the title compound as a clear oil [11.3 g (75% pure), 82%]. 1H NMR (400 MHz, CDCl3) 8.51 (d, J=3.2 Hz, 1H), 8.11 (dd, J=4.4 and 4.4 Hz, 1H), 7.51 (ddd, J=2.8, 3.2 and 2.8 Hz, 1H), 2.71 (s, 3H).

1. temperatureThe reaction was heated
2. temperatureat reflux
3. temperatureAfter heating for 70 hours
4. customto quench
5. customthe reaction
6. temperaturethe mixture was heated
7. temperatureat reflux for 1 hour
8. extractionextracted with ether (3×100 ml)
9. customThe combined organic layers were dried
10. dry with materialover dried over sodium sulfate
11. concentrationconcentrated
12. customAfter removal of solvent
13. customthe resulted residue was purified by column chromatography (hexane-ether=5:1)

ORD record

ord-07a52d8413ce4048a4292271fd30496f

Source dataset

uspto-grants-2012_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08114989B2