Water → 6-iodo-2H-3,1-benzoxazine-2,4(1H)-dione

Participants

Reaction Steps

To a mechanically stirred solution of 26.3 grams of 5-iodo-2-amino benzoic acid (0.1 mol), 10.6 grams of sodium carbonate (0.1 mol), and 250 mL water, cooled to 0° C., was slowly added, via an addition funnel, 80 mL of a 1.93M solution of phosgene in toluene. After 2 hours, the precipitated product was isolated by filtration. The solids were washed with 200 mL water, 300 mL of a 1:1 mixture ethanol and ether, 200 mL of ether, and dried under vacuum to yield 24.3 grams (84%) of 5-iodoisatoic anhydride (264°-268° C., decomposition).

Provenance & Evidence