反应详情

0.5 grams of 7-methoxy-1,4-benzoxazin-3-one (2.8 mmole) was dissolved in 10 ml of dimethylformamide and cooled in an ice bath. 0.17 grams (3.5 mmole) of sodium hydride (60% wt. inn oil) was added, and after 5 minutes 0.8 grams (2.9 mmole) of 3-bromo-5-chloro-benzylbromide was added all at once. The mixture was stirred at ice bath temperature for 1 hour, and then quenched by addition of 1% hydrochloric acid. The product was extracted with ethyl acetate, that was evaporated under reduced pressure to give an oil which was chromatographed via medium pressure eluting with 10% ethyl acetate in hexanes to yield 0.9 grams of 4-(3-bromo-5-chloro-benzyl)-7-methoxy-4H-benzo[1,4]oxazin-3-one as a white solid.

1. temperaturecooled in an ice bath
2. customquenched by addition of 1% hydrochloric acid
3. extractionThe product was extracted with ethyl acetate, that
4. customwas evaporated under reduced pressure
5. customto give an oil which
6. customwas chromatographed via medium pressure
7. washeluting with 10% ethyl acetate in hexanes