反应详情

A mixture of ethyl 8-fluoro-4-hydroxyquinazoline-2-carboxylate (530 mg, 2.2 mmol) and POCl3 (3 mL) was heated under reflux for 5 h. The mixture was concentrated under reduced pressure, and then toluene was twice added and concentrated under reduced pressure. The residue was purified by silica gel chromatography eluting with 0-25% EtOAc/hexanes to afford ethyl 4-chloro-8-fluoroquinazoline-2-carboxylate (365 mg, 65%). 1H NMR (300 MHz, DMSO-d6) δ 1.39 (t, J=7.1 Hz, 3H), 4.46 (q, J=7.1 Hz, 2H), 7.97-8.06 (m, 1H), 8.07-8.16 (m, 1H), 8.18-8.24 (m, 1H).

1. temperaturewas heated
2. temperatureunder reflux for 5 h
3. concentrationThe mixture was concentrated under reduced pressure
4. additiontoluene was twice added
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified by silica gel chromatography
7. washeluting with 0-25% EtOAc/hexanes