Phosphorus oxychloride → 5-Bromo-2-chloro-3-nitropyridine

Participants

Reaction Conditions

Reaction Steps

2-Hydroxy-3-nitro-5-bromopyridine (10 g) was combined with 25 mL of phosphorus oxychloride and 5 g of phosphorus pentachloride. The mixture was heated to 110° C. for 2 h, then cooled to room temperature and poured into ice-water and stirred 30 min. The mixture was extracted with CHCl3, then the combined organics were dried (MgSO4) and concentrated in vacuo. Purification by chromatography through a short plug of SiO2, eluting with 4:1 hexanes:EtOAc afforded 6.72 g of 5-bromo-2-chloro-3-nitro-pyridine.

Provenance & Evidence