反应详情

A mixture of 2-acetylphenoxathiin (4.80 g), sodium hypochlorite solution (95 ml.; 5.7% available chlorine), 4% w/v sodium hydroxide solution (100 ml) and dioxan (100 ml) was mechanically stirred on the steam bath for 5 hr. The solution was poured on to ice and excess hydrochloric acid with stirring. The white precipitate was filtered off and dissolved in hot 4% w/v sodium hydroxide solution (40 ml) and filtered. The sodium salt of the required acid crystallised from the filtrate on cooling and was filtered off, dissolved in boiling water, and the acid precipitated by addition of excess hydrochloric acid. It was filtered off and recrystallised from acetic acid, m.p. 253° C.

1. stirringwith stirring
2. filtrationThe white precipitate was filtered off
3. dissolutiondissolved in hot 4%
4. filtrationfiltered
5. customThe sodium salt of the required acid crystallised from the filtrate
6. temperatureon cooling
7. filtrationwas filtered off
8. dissolutiondissolved
9. customthe acid precipitated by addition of excess hydrochloric acid
10. filtrationIt was filtered off
11. customrecrystallised from acetic acid, m.p. 253° C.