Phosgene → 6-Fluoroisatoic anhydride

Participants

Reaction Steps

Phosgene is conducted at 35°-40° C. for 3 hours into a solution of 23 g (0.148 mol) of 6-fluoroanthranilic acid hydrochloride in a mixture of 300 ml of tetrahydrofuran and 150 ml of 4 N hydrochloric acid. After removal of the phosgene, the mixture is diluted with 500 ml of water and the precipitate is filtered off. There is obtained crude 6-fluoroisatoic acid anhydride of melting point 265°-267° C. (decomposition).

Provenance & Evidence