反应详情

温度

7.5 °C

N-Iodosuccinimide (5.8 g) is added in portions to an ice-cold solution of sulphuric acid (20 mL). The resulting mixture is stirred for 40 min before 3-bromo-2-methyl-benzoic acid (5.0 g) dissolved in sulphuric acid (20 mL) is added at such a rate that the solution temperature maintained below 5° C. The mixture is stirred at 5-10° C. for another 3 h before warming to room temperature over night. Then, the mixture is poured on crushed ice (300 g) and the resultant solution is extracted with ethyl acetate. The combined extracts are washed in succession with aqueous 10% Na2S2O3 solution (2×), water (3×), and brine (1×). After drying (MgSO4) the organic layer, the solvent is evaporated under reduced pressure to give a solid. The solid is triturated with 70° C.-warm water, separated from the water by filtration and dried. After the solid is triturated with little ether, filtered and dried, the product is obtained as a white solid.

1. additionis added at such a rate that the solution temperature
2. temperaturemaintained below 5° C
3. temperaturebefore warming to room temperature over night
4. additionThen, the mixture is poured
5. extractionthe resultant solution is extracted with ethyl acetate
6. washThe combined extracts are washed in succession with aqueous 10% Na2S2O3 solution (2×), water (3×), and brine (1×)
7. dry with materialAfter drying (MgSO4) the organic layer
8. customthe solvent is evaporated under reduced pressure
9. customto give a solid
10. customThe solid is triturated with 70° C.-
11. temperaturewarm water
12. customseparated from the water by filtration
13. customdried
14. customAfter the solid is triturated with little ether
15. filtrationfiltered
16. customdried
17. customthe product is obtained as a white solid