反应详情

温度

0 °C

To a suspension of 2,4-dichloroquinazoline (995 mg, 5.0 mmol) in dry EtOH (100 mL), were added methoxyamine hydrochloride (569 mg, 5.5 mmol) and NaOH (227 mg, 5.5 mmol) in one portion at 0° C. The reaction mixture was stirred at 0° C. for 1 hour, then placed in a refrigerator at 4° C. for 72 h. Upon completion, the reaction was concentrated, and the residue was dissolved in EtOAc and washed with saturated NaHCO3 (1×) and brine (1×). The organic phase was dried over MgSO4, filtered and concentrated. The crude product was purified by preparative HPLC (10-90% CH3CN in H2O) to provide 4-(methoxyamino)quinazolin-2(1H)-one (556 mg, 36%) as an off-white solid. 1H NMR (400 MHz, DMSO-d6) δ3.68 (s, 3H), 7.02 (t, J=7.4 Hz, 1H), 7.35 (d, J=7.9 Hz, 1H), 7.52 (ddd, J=8.1, 7.0, 1.5 Hz, 1H), 7.77 (dd, J=7.8, 1.4 Hz, 1H), 10.13 (br s, 1H), 10.89 (br s, 1H). MS 192.2 (MH+).

1. waitplaced in a refrigerator at 4° C. for 72 h
2. concentrationUpon completion, the reaction was concentrated
3. dissolutionthe residue was dissolved in EtOAc
4. washwashed with saturated NaHCO3 (1×) and brine (1×)
5. dry with materialThe organic phase was dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. customThe crude product was purified by preparative HPLC (10-90% CH3CN in H2O)