Diphosgene → 6-methylsulfanyl-1H-benzo[d][1,3]oxazine-2,4-dione

Participants

Reaction Steps

To a stirred mixture of 9.16 parts of 2-amino-5-(methylthio)benzoic acid and 100 parts of 1,4-dioxane were added dropwise slowly 9.8 parts of trichloromethyl carbonochloridate. Upon completion, stirring was continued for 2 hours. The reaction mixture was evaporated. The residue was crystallized from acetonitrile. The product was filtered off and dried, yielding 8 parts (76%) of 6-(methylthio)-2H-3,1-benzoxazine-2,4(1H)-dione; mp. 219.4° C. (intermediate 153).

Provenance & Evidence