Triphosgene → 5-Methoxy-2H-3,1-benzoxazine-2,4(1H)-dione

Participants

Reaction Conditions

Reaction Steps

To a stirred warm (50° C.) solution of 2-amino-6-methoxybenzoic acid (2.70 g, 16.2 mM) in tetrahydrofuran (25 mL) under a nitrogen atmosphere was added bis(trichloromethyl)carbonate (1.60 g, 5.38 mM), whereupon a tan precipitate formed. The reaction mixture was maintained at 50° C. for 30 min, cooled, rewarmed to 50° C. for 30 min, filtered cool and dried to provide the title compound (2.95 g, 94.6%) as an off-white solid; MS(CI): 194 (M+H).

Provenance & Evidence