反应详情

A mixture of 3-(3-bromo-2-methylphenyl)-8-methoxyquinazoline-2,4(1H,3H)-dione (535 mg, 1.48 mmol), iodomethane (0.185 mL, 2.96 mmol) and Cs2CO3 (965 mg, 2.96 mmol) in THF (20 mL) was stirred at room temperature overnight. The mixture was filtered and concentrated. The residue was dissolved in DCM, washed sequentially with saturated aqueous NaHCO3 and water, dried and concentrated. The residue was purified by column chromatography on silica gel (40 g silica), eluting with EtOAc-hexanes (gradient from 0-100%), to give 3-(3-bromo-2-methylphenyl)-8-methoxy-1-methylquinazoline-2,4(1H,3H)-dione (442 mg). Mass spectrum m/z 375, 377 (M+H)+. 1H NMR (400 MHz, chloroform-d) δ 7.90 (dd, J=7.2, 2.3 Hz, 1H), 7.66 (dd, J=8.0, 1.2 Hz, 1H), 7.31-7.22 (m, 2H), 7.22-7.19 (m, 1H), 7.17-7.13 (m, 1H), 3.97 (s, 3H), 3.89 (s, 3H), 2.23 (s, 3H).

1. filtrationThe mixture was filtered
2. concentrationconcentrated
3. dissolutionThe residue was dissolved in DCM
4. washwashed sequentially with saturated aqueous NaHCO3 and water
5. customdried
6. concentrationconcentrated
7. customThe residue was purified by column chromatography on silica gel (40 g silica)
8. washeluting with EtOAc-hexanes (gradient from 0-100%)