Acetyl chloride → 7-Bromo-2-methylquinazolin-4(3H)-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 0.81 g 4-bromoanthranilic acid (J. Org. Chem. 1997, 62, 1240-1256), 39 mg 4-(dimethylamino)pyridine and 2.09 ml triethylamine in dry dimethylformamide is added dropwise 0.69 ml acetylchloride at 3° C. for 20 min. in an ice-water bath under argon. The reaction mixture is then heated at 90° C. for 3 h. and 1.08 g ammonium carbonate is added portionwise over 10 min., and the mixture is stirred at the same temperature for 1 h. After cooling, the mixture is poured onto 20 ml water and the precipitate is filtered, washed with water and dried in vacuo to give 0.46 g (51%) of crude 7-Bromo-2-methyl-3H-quinazolin-4-one as a light-brown solid. Mp. >191° C. (dec.). MS (EI): peaks at m/e: 240(M+, 100%), 223 (14%), 197(18%).

Provenance & Evidence