1-Acetyl-3-methylurea

To a solution of acetamide (15 g, 0.25 mol) in bromine (22 g),warmed slowly with stirring, was added dropwise via syringe sodium hydroxide (10 g, 0.25 mol) in water (25 ml). The mixture was heated to bubble up. After 3 minutes additional heating, the reaction mixture was cooled down with ice bath, filtered and washed with ice water (3 × 10 ml) to give acetyl methylurea (12 g) as a white powder, which was used without further purification.