Anthranilic Acid → 5-methyl-2,4-dihydro-1H-3,1-benzoxazine-2,4-dione

Participants

Reaction Steps

To a suspension of CDI (49.35 g, 305 mmol) in 100 mL of dioxane was added at room temperature a solution of the anthranilic acid (20 g, 132 mmol) in 100 mL of dioxane over 30 minutes. The reaction was stirred at ambient temperature until the mild exotherm subsided. The reaction mixture was filtered through a bed of silica gel (dioxane), concentrated then diluted with about 200 mL of water. The resulting precipitate was filtered, washed with water and dried affording 20.3 g (87%) of 5-methyl-2H-3,1-benzoxazin-2,4 (1H)-dione.

Provenance & Evidence