反应详情

A solution of ethyl 2-benzamido-3-oxobutanoate (13.0 g, 0.052 mol) in phosphorus oxychloride (100 mL) was heated under reflux for 1.5 h, then cooled and concentrated under reduced pressure to a brown syrup which was dissolved in dichloromethane (250 mL). The solution was washed with water, saturated Na2CO3 and brine successively, then dried over anhydrous Na2SO4 and concentrated to give ethyl 5-methyl-2-phenyloxazole-4-carboxylate as a brown oil (11.0 g, 91% yield).

1. temperatureunder reflux for 1.5 h
2. temperaturecooled
3. concentrationconcentrated under reduced pressure to a brown syrup which
4. dissolutionwas dissolved in dichloromethane (250 mL)
5. washThe solution was washed with water, saturated Na2CO3 and brine successively
6. dry with materialdried over anhydrous Na2SO4
7. concentrationconcentrated