反应 #2139945

反应方程式

carbon dioxide

LDA

4-bromo-2-fluorotoluene

hydrochloric acid

→

6-bromo-2-fluoro-3-methylbenzoic acid

收率 49.2%

溶剂

THF

THF

反应条件

后处理

1. 1
   萃取the solution was extracted with MTB ether
2. 2
   洗涤the combined organic phases were washed with water
3. 3
   干燥dried over sodium sulfate
4. 4
   其他evaporated under reduced pressure
5. 5
   其他Crystallisation of the crude product from 1-chlorobutane

实验过程

50 ml (0.385 mol) of 4-bromo-2-fluorotoluene were dissolved in 750 ml of THF, and 231 ml (0.462 mol) of a 2 M solution of LDA in THF were added dropwise at −70° C. After 70 minutes, 37.2 g (0.846 mol) of carbon dioxide were passed in, and the batch was allowed to thaw. After acidification using conc. hydrochloric acid, the solution was extracted with MTB ether, and the combined organic phases were washed with water, dried over sodium sulfate and evaporated under reduced pressure. Crystallisation of the crude product from 1-chlorobutane gave 44.1 g (49%) of 6-bromo-2-fluoro-3-methylbenzoic acid as white crystals.

来源