반응 #1807213

반응 방정식

2-amino-4-fluorobenzylsulfonate

→

1,3-dihydro-6-fluoro-2,1-benzisothiazole 2,2-dioxide

수율 31.7%

용매

phosphorous oxychloride

반응 조건

후처리

1. 1
   온도the mixture was heated
2. 2
   온도under reflux for 6 hours
3. 3
   농축The reaction mixture was concentrated in vacuo
4. 4
   workup.ADDITIONthe resulting grease was poured into ice-water mixture
5. 5
   workup.ADDITIONA sodium hydroxide solution was added to the mixture at 0° C. until the mixture
6. 6
   여과Insoluble material was filtered off
7. 7
   세척washed with water
8. 8
   workup.ADDITIONThe filtrate was treated with aqueous hydrochloric acid solution (pH=2.5)
9. 9
   기타The crude product was separated by filtration
10. 10
    workup.ADDITIONEthyl acetate was added to the precipitate
11. 11
    여과the insoluble material was filtered off
12. 12
    농축The filtrate was concentrated in vacuo

실험 절차

2-amino-4-fluorobenzylsulfonate (11.0 g) was added to phosphorous oxychloride (100 ml) at 50° C. and the mixture was heated under reflux for 6 hours. The reaction mixture was concentrated in vacuo and the resulting grease was poured into ice-water mixture. A sodium hydroxide solution was added to the mixture at 0° C. until the mixture was basic. Insoluble material was filtered off and washed with water. The filtrate was treated with aqueous hydrochloric acid solution (pH=2.5). The crude product was separated by filtration. Ethyl acetate was added to the precipitate and the insoluble material was filtered off. The filtrate was concentrated in vacuo, to give 1,3-dihydro-6-fluoro-2,1-benzisothiazole 2,2-dioxide (3.2 g)

출처