反应详情

350 ml of oleum (30% by weight) was cooled down below 0° C. using an ice bath, 99.6 g (0.368 mol) of 4,4'-diamino-6-carbamoyl benzanilide in a powder form was added below 5° C. with stirring. The stirring was continued to the next day, and the solution was neutralized by adding 1100 ml of NH4OH (28% by weight) already cooled down to -5° to 0° C. The solution was sufficiently washed to remove salt by filtering and washed with a small amount of warm ethanol and then dried in a vacuum oven at 80° C. The dried reactant which was mixed with by-products was extracted by soxlet and treated with the activated carbon and then ethanol was added to recrystallize in the mixture solvent (acetone:ethanol=1:1). The light yellow-scalelike crystal was filtered and dried in a vacuum oven at 80° C. The light yellow-scalelike crystal was extracted again by soxlet with acetone and treated with the activated carbon. And then the white-scalelike crystal obtained by recrystalling in the mixture solvent (acetone:ethanol=1:1) was dried in a vacuum oven at 80° C. (40 g of the raw material was obtained and the boiling point thereof was 250° to 251° C.).

1. temperaturealready cooled down to -5° to 0° C
2. washThe solution was sufficiently washed
3. customto remove salt
4. filtrationby filtering
5. washwashed with a small amount of warm ethanol
6. customdried in a vacuum oven at 80° C
7. additionThe dried reactant which was mixed with by-products
8. extractionwas extracted by soxlet
9. additiontreated with the activated carbon
10. additionethanol was added
11. customto recrystallize in the mixture solvent (acetone:ethanol=1:1)
12. filtrationThe light yellow-scalelike crystal was filtered
13. customdried in a vacuum oven at 80° C
14. extractionThe light yellow-scalelike crystal was extracted again by soxlet with acetone
15. additiontreated with the activated carbon
16. customAnd then the white-scalelike crystal obtained
17. dry with materialwas dried in a vacuum oven at 80° C. (40 g of the raw material
18. customwas obtained
19. customthereof was 250° to 251° C.