反応 #54362

反応方程式

potassium hydride

benzyl bromide

4-bromoresorcinol

N,N-dimethylformamide

→

3-benzyloxy-4-bromophenol

溶媒

ether

water

反応条件

後処理

1. 1
   その他To a 0° C.
2. 2
   workup.ADDITIONadded to 200 ml
3. 3
   抽出The ether extract
4. 4
   洗浄is washed twice with 200 ml
5. 5
   乾燥portions of water, dried over magnesium sulfate
6. 6
   その他evaporated to an oil
7. 7
   その他The crude oil is purified via column chromatography on 400 g
8. 8
   洗浄of silica gel eluted with 25% ether-pentane
9. 9
   その他to yield
10. 10
    洗浄(in order of elution) 2.2 g

実験手順

To a 0° C. slurry of 1.7 g. (42.5 mmoles) of potassium hydride in 35 ml. of N,N-dimethylformamide is slowly added a solution of 7.22 g. (38.2 mmoles) of 4-bromoresorcinol. The resultant mixture is stirred for 30 minutes and then 4.54 ml. (38.2 mmoles) of benzyl bromide is slowly added. The reaction mixture is stirred 3 hours longer at 0° C. and then added to 200 ml. of cold water and 200 ml. of ether. The ether extract is washed twice with 200 ml. portions of water, dried over magnesium sulfate and evaporated to an oil. The crude oil is purified via column chromatography on 400 g. of silica gel eluted with 25% ether-pentane to yield (in order of elution) 2.2 g. (16%) of 2,4-dibenzyloxybromobenzene, 0.21 g. (2%) of 5-benzyloxy-2-bromophenol and 3.52 g. (33%) of 3-benzyloxy-4-bromophenol.

出典