Phosphorus pentachloride → 4-Chloro-3-nitropyridine

Participants

Reaction Steps

To a solution of 4-hydroxy-3-nitro-pyridine (2 g, 14 mmol) in POCl3 (6 mL) was added PCl5 (2.5 g, 12 mmol). The mixture was heated to reflux for 3 hours. The solvent was evaporated and the residue was cooled with ice-water and vigorously stirred with water (3 mL) and CHCl3 (6 mL). The aqueous was extracted CHCl3 (5×5 mL). The organic phase was combined and dried over MgSO4. After filtration, the solvent was removed to afford the product 4-Chloro-3-nitro-pyridine (2.24 g, 99%). 1H NMR (CDCl3, 400 Hz) δ 9.13 (s, 1H), 8.70 (d, J=5.2 Hz, 1H), 7.55 (d, J=5.6 Hz, 1H). MS (ESI+) [M+H]+ 159.

Provenance & Evidence