6-Amino-3-chloropyridazine → 3-Amino-4-bromo-6-chloropyridazine

Participants

Reaction Steps

Bromine (9.71 g, 3.15 mL, 60.75 mmol) was added dropwise to a mixture of 3-amino-6-chloropyridazine (7.87 g, 60.75 mmol) in methanol (115 mL) and sodium bicarbonate (10.22 g, 121.67 mmol). The resultant mixture was stirred at room temperature for 16 hours and then filtered. Water (500 mL) was added to the filtrate and the solution was extracted with ethyl acetate (3×500 mL). The organic layers were combined and concentrated in vacuo. The resulting residue was purified by flash chromatography eluting with 1/1 hexane/ethyl acetate to give 5.40 g (43%) 3-amino-4-bromo-6-chloropyridazine.

Provenance & Evidence