4,5-Dimethoxyanthranilic acid → 6,7-Dimethoxy-2H-3,1-benzoxazine-2,4(1H)-dione

Participants

Reaction Steps

10.0 g (50.7 mmol) 2-Amino-4,5-dimethoxy-benzoic acid were dissolved in 150 ml tetrahydrofuran. 6.52 g (22.0 mmol) triphosgene were added and the solution was boiled for 3 h. After equilibration to room temperature the reaction mixture was poured on a water/ice mixture. The residue was filtrated and rinsed with methanol.

Provenance & Evidence