反应详情

To an ice-bath cooled solution (5° C.) of 8-amino-1,3,6-naphthalenetrisulfonic acid trisodium salt and 6.7 g of sodium acetate trihydrate in 100 ml of water is added 8.8 g of 4-nitro-2-sulfobenzoic acid anhydride. The mixture is stirred vigorously for 10 minutes and is filtered. The filtrate is cooled in an ice bath and diluted with 500 ml of cold ethyl alcohol. The mixture is filtered and the product is washed with ethyl alcohol and ether and then is dried. The product is dissolved in 50 ml of warm water and is stirred for 10 minutes after the addition of one ml of acetone. The mixture is treated with activated charcoal, filtered through diatomaceous earth and is washed with 20 ml of water. The filtrate is cooled in an ice bath and acidified with 1.5 ml of concentrated hydrochloric acid. The solution is diluted with 500 ml of cold ethyl alcohol, and the precipitated material is filtered, washed with ethanol followed by ether and dried. The above purification process is repeated without acidification. The product obtained is dried overnight at 100° C. to give 18.5 g of 8-(4-nitro-2-sulfobenzamido)-1,3,6-naphthalenetrisulfonic acid tetrasodium salt.

1. filtrationis filtered
2. temperatureThe filtrate is cooled in an ice bath
3. additiondiluted with 500 ml of cold ethyl alcohol
4. filtrationThe mixture is filtered
5. washthe product is washed with ethyl alcohol and ether
6. customis dried
7. dissolutionThe product is dissolved in 50 ml of warm water
8. stirringis stirred for 10 minutes
9. additionafter the addition of one ml of acetone
10. additionThe mixture is treated with activated charcoal
11. filtrationfiltered through diatomaceous earth
12. washis washed with 20 ml of water
13. temperatureThe filtrate is cooled in an ice bath
14. additionThe solution is diluted with 500 ml of cold ethyl alcohol
15. filtrationthe precipitated material is filtered
16. washwashed with ethanol
17. customdried
18. customThe above purification process
19. customThe product obtained
20. customis dried overnight at 100° C.