8-Bromo-6-fluoro-2-methylquinazolin-4(3H)-one

1352717-90-8

1352717-91-9

8-Bromo-6-fluoro-2-methyl-4H-benzo[d][1,3]oxazin-4-one (12,466 mg, 1.81 mmol) was used as a feedstock and suspended in 28% v/v aqueous ammonia solution (8 mL). The reaction mixture was stirred at reflux for 1.5 h at 100 °C. After completion of the reaction, the reaction mixture was concentrated. The resulting precipitate was collected by filtration, washed with distilled water (20 mL) and dried to constant weight to afford 8-bromo-6-fluoro-2-methylquinazolin-4(3H)-one (14,342 mg, 73.7% yield) as a pale white solid. The product could be used in subsequent reactions without further purification. The product was characterized by the following data: retention time (t R) = 2.40 min, purity = 100%; no ions detected by ESI+MS; 1H NMR (DMSO-d6) δ (ppm): 2.39 (s, 3H), 7.80 (dd, J = 3.0 Hz, JH-F = 8.2 Hz, 1H), 8.13 (dd, J = 2.7 Hz, JH-F = 8.2 Hz, 1H), 12.54 (br s, 1H); 13C NMR (DMSO-d6) δ (ppm): 21.6, 110.7 (d, JC-F = 23.0 Hz), 122.9 (d, JC-F = 9.7 Hz), 123.0 (d, JC-F = 8.8 Hz), 126.5 (d, JC-F = 26.6 Hz), 143.9 (d, JC-F = 2.7 Hz), 155.3 (d, JC-F = 1.8 Hz), 159.0 (d, JC-F = 247.7 Hz), 161.1 (d, JC-F = 3.5 Hz); HRMS (ESI+) m/z calculated value of C9H7N2BrF: 256.97203, measured value: 256.97205.