反応 #1447105

反応方程式

N-Iodosuccinimide

3-bromo-2-methyl-benzoic acid

→

3-Bromo-5-iodo-2-methyl-benzoic acid

溶媒

sulphuric acid

sulphuric acid

反応条件

後処理

1. 1
   workup.ADDITIONis added at such a rate that the solution temperature
2. 2
   温度maintained below 5° C
3. 3
   温度before warming to room temperature over night
4. 4
   workup.ADDITIONThen, the mixture is poured
5. 5
   抽出the resultant solution is extracted with ethyl acetate
6. 6
   洗浄The combined extracts are washed in succession with aqueous 10% Na2S2O3 solution (2×), water (3×), and brine (1×)
7. 7
   乾燥After drying (MgSO4) the organic layer
8. 8
   その他the solvent is evaporated under reduced pressure
9. 9
   その他to give a solid
10. 10
    その他The solid is triturated with 70° C.-
11. 11
    温度warm water
12. 12
    その他separated from the water by filtration
13. 13
    その他dried
14. 14
    その他After the solid is triturated with little ether
15. 15
    ろ過filtered
16. 16
    その他dried
17. 17
    その他the product is obtained as a white solid

実験手順

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.

出典