反应详情

To a suspension of 2-(4-chlorophenyl)-6-[1-(ethoxycarbonyl)ethoxyl]-4-methyl-2H-1,2,4-benzothiadiazine-3(4H)-one 1,1-dioxide (400 mg) in a mixture of ethanol (5 ml) and water (5 ml) was added aqueous 1N-sodium hydroxide solution (1.1) ml in one portion. The mixture was refluxed for half hour and concentrated in vacuo. The residue was dissolved in water and washed with ethyl ether. The aqueous layer was acidified with hydrochlonic acid. The separated oil was extracted with ethyl acetate. The organic layer was washed with brine, dried, and evaporated to dryness. The residue was crystallized from a mixture of n-hexane and ethyl acetate to yield 2-(4-chlorophenyl)-6-(1-carboxyethoxy)-4-methyl-2H-1,2,4-benzothiadiazine-3(4H)-one 1,1-dioxide (240 mg).

1. temperatureThe mixture was refluxed for half hour
2. concentrationconcentrated in vacuo
3. dissolutionThe residue was dissolved in water
4. washwashed with ethyl ether
5. extractionThe separated oil was extracted with ethyl acetate
6. washThe organic layer was washed with brine
7. customdried
8. customevaporated to dryness
9. customThe residue was crystallized from a mixture of n-hexane and ethyl acetate