Triphosgene → 5-Chloro-3-methyl isatoic anhydride

Participants

Reaction Steps

A mixture of 1.85 g of 2-amino-5-chloro-3-methylbenzoic acid, 0.90 g of triphosgene and 10 ml of tetrahydrofuran was stirred at room temperature for 5 hours. The reaction mixture was concentrated under reduced pressure, and a precipitated crystal was washed with water to obtain 1.20 g of 6-chloro-8-methyl-1H-benzo[d]-1,3-oxazine-2,4-dione of the formula:

Provenance & Evidence