反应详情

Anthranilic acid (274.3 g) and acetic anhydride (1.1 L) were combined then heated at reflux for 3.5 hours. The reaction mixture was concentrated under vacuum. The residue was combined with methanol (550 mL) then concentrated under vacuum to provide 2-methyl-4-oxo-3,1-benzoxazine as a brown oil.

1. temperatureat reflux for 3.5 hours
2. concentrationThe reaction mixture was concentrated under vacuum
3. concentrationthen concentrated under vacuum