Acetic Anhydride → 6-methoxy-2-methyl-4H-benzo[d][1,3]oxazin-4-one

Participants

Reaction Steps

A solution of 5-methoxyanthranilic acid (7.8 g, 46.5 mmol) was refluxed in acetic anhydride (60 mL) for 2 h 15 before being cooled and concentrated under reduced pressure. The crude residue was then concentrated twice in the presence of toluene before being filtered and washed with ether to yield to the title compound (6.8 g, 77% yield) as a beige solid; LC/MS: m/z 192 [M+H]+, Rt 1.69 min.

Provenance & Evidence