Water → 8-Bromo-7-chloro-2-methoxy-1,5-naphthyridine

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-chloro-6-(methyloxy)-1,5-naphthyridin-4(1H)-one (3-chloro-6-(methyloxy)-1,5-naphthyridin-4-ol, for a synthesis see WO2004058144, Example 1(a) (5.1 g, 24.28 mmol) in DMF (50 ml) at 0° C. was added phosphorous tribromide dropwise (2.77 ml, 29.1 mmol) keeping the internal temperature below 20° C. The reaction mixture was then stirred at 10° C. for 0.5 h and then at 25° C. for 1 h. The mixture was then poured on 200 ml of water and the water basified to neutral pH with potassium carbonate. The solid formed was filtered off, washed with water and dried in the oven and then in the desiccator to afford the desired compound (5.8 g, 88%).

Provenance & Evidence