Phosphorus oxychloride → 7-Bromo-2-chloro-1,6-naphthyridine

Participants

Reaction Conditions

Reaction Steps

7-Bromo-1,6-naphthyridin-2(1H)-one (Preparation 67, 800 mg 3.55 mmole) was treated with phosphorus oxychloride (18 mL) and catalytic DMF (2 drops). The reaction was heated at 80° C. for 2.5 hours. The phosphorus oxychloride was evaporated and the residue was azeotroped with toluene (15 mL). The solid was partitioned between ethyl acetate (50 mL) and saturated aqueous sodium bicarbonate solution (30 mL) with ice (10 g). The aqueous layer was washed with EtOAc, the organic layers combined, washed with sodium bicarbonate solution, brine, dried over sodium sulphate and concentrated in vacuo to afford the title compound (826 mg, 95%).

Provenance & Evidence