反应详情

温度

0 °C

To a cooled solution of 2H-1,4-benzoxazin-3(4H)-one (11.93 g, 80 mmol) in N,N-dimethylformamide (120 ml) was added sodium hydride (60% dispersion in mineral oil, 3.2 g, 80 mmol) in portions between 0° C. and 5° C. (1 h). The mixture was stirred 1 h at 0° C. To the cooled mixture was added ethyl iodide (13.7 g, 88 mmol) dropwise. The ice bath was removed and the mixture was stirred at r.t. for 17 h. The mixture was poured on water and extracted twice with AcOEt. The organic layers were washed with brine and water, dried (MgSO4) and concentrated. The crude product was purified by column chromatography (silica gel, heptane/AcOEt 9:1) to give the title compound (13.3 g) as colorless oil.

1. customThe ice bath was removed
2. stirringthe mixture was stirred at r.t. for 17 h
3. additionThe mixture was poured on water
4. extractionextracted twice with AcOEt
5. washThe organic layers were washed with brine and water
6. dry with materialdried (MgSO4)
7. concentrationconcentrated
8. customThe crude product was purified by column chromatography (silica gel, heptane/AcOEt 9:1)