2-Chloro-3-methyl-5-nitropyridine → 2-Fluoro-3-methyl-5-nitropyridine

Participants

Reaction Steps

2-Chloro-3-methyl-5-nitropyridine (15.0 g, 86.9 mmol; from Maybridge Chemical Co.), KF (12 g, 258 mmol), and tetraphenylphosphonium bromide (20 g, 47.7 mmol) were combined in 200 mL of acetonitrile and heated at reflux for 4 days. The mixture was diluted with Et2O (500 mL), filtered, and the solution was concentrated. The residue was triturated with hot hexane, then the combined hexane solutions were concentrated to give 8.4 g (60%) of the title compound: 1H NMR (DMSO-d6, 300 MHz) δ8.95 (dd, J=1.6 Hz, 1H), 8.43 (m, 1H), 2.42 (s, 1H); MS (CI/NH3) m/z: 157 (M+H)+.

Provenance & Evidence