反应详情

At 20° to 28° C. and while stirring, 42.5 g of ammonia was gassed into a mixture of 252.6 g (1 mol) of methyl 2-chlorosulfonyl-6-fluorobenzoate in 700 ml of anhydrous tetrahydrofuran. After the mixture had been stirred for an hour at 25° C., the precipitate was filtered off, dissolved in water, and extracted once with ethyl acetate. Acidification of the aqueous phase with concentrated hydrochloric acid gave 4% of theory of 4-fluoro-1,2-benzisothiazol-3-one-1,1-dioxide of m.p. 210° to 212° C.

1. stirringAfter the mixture had been stirred for an hour at 25° C.
2. filtrationthe precipitate was filtered off
3. dissolutiondissolved in water
4. extractionextracted once with ethyl acetate