反应详情

To a biphasic mixture of NaOH 1 N aq. (10.79 mL, 10.79 mmol) and 11 mL THF was added 8-bromo-2,4-dichloroquinazoline (407b, 1.50 g, 5.40 mmol) in one portion. The reaction became dark red. After 20 min the reaction was checked by LC/MS and judged complete. The reaction was cooled in an ice/water bath and acidified with AcOH. The reaction was concentrated to ½ volume on rotovap (precipitate observed) and cooled in an ice/water bath. The slurry was filtered and the solid rinsed with 2× water. The orange solid was collected and dried in vacuo to give 8-bromo-2-chloroquinazolin-4-ol (1.10 g, 4.24 mmol, 79% yield) as an orange solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 13.49 (1H, br. s.), 8.15 (1H, dd, J=7.8, 1.4 Hz), 8.09 (1H, dd, J=7.9, 1.5 Hz), 7.45 (1H, t, J=7.8 Hz). m/z (ESI, +ve ion) 258.9/260.9 (M+H)+.

1. temperatureThe reaction was cooled in an ice/water bath
2. concentrationThe reaction was concentrated
3. temperaturecooled in an ice/water bath
4. filtrationThe slurry was filtered
5. washthe solid rinsed with 2× water
6. customThe orange solid was collected
7. customdried in vacuo