反応 #56541

反応方程式

magnesium

hydrochloric acid

p-bromochlorobenzene

o-chlorobenzaldehyde

p-bromochlorobenzene

→

2,4'-dichlorobenzhydrol

溶媒

water

ether

ether

反応条件

後処理

1. 1
   その他When the Grignard reaction
2. 2
   その他the heat is removed
3. 3
   workup.ADDITIONWhen the addition
4. 4
   温度the reaction is heated
5. 5
   温度at reflux for 2 hours
6. 6
   温度cooled
7. 7
   温度The reaction is refluxed for 2 hours
8. 8
   温度cooled
9. 9
   その他the organic phase is separated
10. 10
    抽出The aqueous layer is extracted with ether
11. 11
    workup.ADDITIONthe extract is added to the organic phase
12. 12
    洗浄This solution is washed with water
13. 13
    乾燥dried over anhydrous magnesium sulfate
14. 14
    濃縮concentrated
15. 15
    その他to give an oily solid
16. 16
    その他The material is crystallized from petroleum ether
17. 17
    その他to give 109.4 g

実験手順

To 12.7 g. (0.52 moles) of magnesium turnings in 200 ml. of anhydrous ether is added 10.0 g. (0.052 moles) of p-bromochlorobenzene, and the mixture is warmed to reflux. When the Grignard reaction begins, the heat is removed and 80.0 g. (0.47 moles) of additional p-bromochlorobenzene in 80 ml. of ether is added dropwise as the refluxing continues. When the addition is completed, the reaction is heated at reflux for 2 hours, cooled, and 73.4 g. (0.52 moles) of o-chlorobenzaldehyde are slowly added. The reaction is refluxed for 2 hours, cooled and poured into iced water. The resulting mixture is made acidic with hydrochloric acid, and the organic phase is separated. The aqueous layer is extracted with ether, and the extract is added to the organic phase. This solution is washed with water, dried over anhydrous magnesium sulfate and concentrated to give an oily solid. The material is crystallized from petroleum ether to give 109.4 g. (83%) of the product, mp 68°-70°.

出典