反应详情

To a slurry of 8-bromo-2,4-dichloroquinazoline (407b; 0.50 g, 1.80 mmol) in 2 mL THF at 0° C. was added ammonium hydroxide, 28% ammonia in water (3.25 mL, 23.39 mmol). The reaction was sealed and the ice/water bath was removed. The heterogeneous reaction was stirred rapidly. In the morning starting material was still evident. 2 mL THF and 1 mL 28% ammonia in water were added and the reaction became homogeneous. After 1 h, reaction was checked and judged complete. The reaction was partitioned between water and DCM. The layers were separated and the aqueous layer was filtered through Celite and the filtrate was extracted 2×DCM and the combined organics were dried over anhydrous Na2SO4, filtered, and concentrated in vacuo to give 8-bromo-2-chloroquinazolin-4-amine (0.318 g, 1.23 mmol, 68% yield) as an orange solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 8.52 (2H, br. s.), 8.24 (1H, d, J=8.4 Hz), 8.14 (1H, d, J=7.6 Hz), 7.42 (1H, t, J=7.9 Hz). m/z (ESI, +ve ion) 257.9/259.9 (M+H)+.

1. customThe reaction was sealed
2. customthe ice/water bath was removed
3. customThe heterogeneous reaction
4. customreaction
5. customThe reaction was partitioned between water and DCM
6. customThe layers were separated
7. filtrationthe aqueous layer was filtered through Celite
8. extractionthe filtrate was extracted 2×DCM
9. dry with materialthe combined organics were dried over anhydrous Na2SO4
10. filtrationfiltered
11. concentrationconcentrated in vacuo