反应 #543558

反应方程式

carbonate

p-arsanilic acid

Bromoacetyl bromide

carbon dioxide

Sodium carbonate

bromoacetyl bromide

sulfuric acid

→

4-(N-(bromoacetyl)amino)phenylarsonic Acid

溶剂

dichloromethane

dichloromethane

dichloromethane

water

water

反应条件

后处理

1. 1
   workup.DISSOLUTIONhad dissolved
2. 2
   workup.STIRRINGto stir for 30 mins
3. 3
   过滤if necessary, was filtered
4. 4
   其他to remove any undissolved solid
5. 5
   其他The solution was transferred to a separating funnel
6. 6
   workup.ADDITIONice chips were added
7. 7
   workup.STIRRINGThe mixture was cautiously shaken, with frequent venting
8. 8
   workup.WAITAfter 1 to 2 mins
9. 9
   workup.STIRRINGmore vigorous shaking
10. 10
    其他the aqueous layer transferred to a 1 L flask
11. 11
    其他precipitation of the white product required
12. 12
    workup.ADDITIONaddition of acid until the solution
13. 13
    其他The crude product was collected
14. 14
    其他dried at the pump
15. 15
    其他typically in yields of 50% to 75%

实验过程

Sodium carbonate (40.14 g, 378.7 mmol) was added to water (200 mL) and stirred at room temperature until all solids had dissolved. To the stirred carbonate solution was added p-arsanilic acid (29.99 g, 138.2 mmol), portionwise, and the volume of the solution made up to 300 mL with addition of more water. The solution (pH 10 to 11) was allowed to stir for 30 mins, and if necessary, was filtered to remove any undissolved solid before being refridgerated for 2 to 3 hours. The solution was transferred to a separating funnel and ice chips were added. Bromoacetyl bromide (15 mL, 34.76 g, 172.1 mmol) was diluted in dichloromethane (50 mL) and approximately half of the dichloromethane solution was added carefully to the cold aqueous solution. The mixture was cautiously shaken, with frequent venting to avoid excessive build up of pressure. After 1 to 2 mins, the evolution of carbon dioxide had subsided, and more vigorous shaking was undertaken. The remaining portion of bromoacetyl bromide was carefully added and the procedure repeated. When the reaction was over, the solution was found to be pH 7. The lower dichloromethane layer was discarded, and the aqueous layer transferred to a 1 L flask and carefully acidified by dropwise addition of 98% sulfuric acid. Complete precipitation of the white product required addition of acid until the solution was approximately pH 1. The crude product was collected and dried at the pump, typically in yields of 50% to 75%. 1H-NMR (d6-DMSO): δ 4.09 (s, 2H), 7.73 (d, J=9 Hz, 2H), 7.83 (d, J=9 Hz, 2H), 10.87 (s, 1H). 13C-NMR (d6-DMSO): δ 30.53, 119.97, 127.34, 131.56, 143.08, 166.00 ppm.

来源