Acetic Anhydride → 4-Acetyl-6-methoxy-1H-2-benzopyran-1,3(4H)-dione

Participants

Reaction Steps

Following a literature procedure (Ind. J. Chem. Sec. B, 1986, 25B, 640-643), 2-carboxymethyl-4-methoxybenzoic acid (41; 1.0 g; 4.8 mmol) was dissolved in a mixture of pyridine (1.4 mL) and acetic anhydride (8.6 mL; 9.3 g; 91 mmol) then stirred for 3 h during which time a solid had formed. The suspension was diluted with diethyl ether, filtered and the filter cake washed with diethyl ether. Yield: 905 mg (81%) of the title compound.

Provenance & Evidence