2,4-Dichloro-6-methoxyquinazoline → 2-Chloro-6-methoxyquinazoline

Participants

Reaction Steps

To a solution of 2,4-dichloro-6-methoxyquinazoline (400 mg, 1.75 mmol) in CH2Cl2 (10 mL) was added brine (10 mL) containing 9% NH3.H2O. Then zinc powder (336 mg, 5.25 mmol) was added and the mixture was refluxed for 2 hours. The mixture was diluted with CH2Cl2 (50 mL) and filtered off, the filtrate was neutralized by 2M HCl to pH 7. The aqueous layer extracted with CH2Cl2 (20 mL×2), the combined organic layer washed with brine (30 mL), dried over Na2SO4, filtered and concentrated to give the crude product, which was purified by silica gel column (PE/EtOAc=5/1) to give Intermediate 8 (232 mg, yield 68%). 1H NMR (CDCl3 300 MHz): δ 9.20 (s, 1H), 7.90 (d, J=9.3 Hz, 1H), 7.40 (dd, J=9.3, 2.7 Hz, 1H), 7.15 (d, J=3.0 Hz, 1H), 3.95 (s, 3H).

Provenance & Evidence