تفاعل #2139947

معادلة التفاعل

4-pentylcyclohexanone

n-butyllithium

1-bromo-3-fluoro-4-iodobenzene

hydrochloric acid

→

4-bromo-2-fluoro-1-(4-pentylcyclohex-1-enyl)benzene

المردود 58.0%

المذيبات

tetrahydrofuran

hexane

tetrahydrofuran

water

ظروف التفاعل

المعالجة

1. 1
   workup.WAITthe batch was left
2. 2
   workup.WAITto stirr for 60 minutes
3. 3
   أخرىThe organic phase was separated off
4. 4
   غسيلwashed with water
5. 5
   تجفيفdried over sodium sulfate
6. 6
   أخرىthe solvent was removed under reduced pressure
7. 7
   workup.DISSOLUTIONThe crude product was subsequently dissolved in 1.4 l of toluene
8. 8
   workup.ADDITIONafter addition of 6 g of toluenesulfonic acid
9. 9
   درجة الحرارةheated on a water
10. 10
    أخرىseparator until water of reaction
11. 11
    أخرىno longer separated off
12. 12
    غسيلThe solution was washed with water
13. 13
    أخرىevaporated
14. 14
    ترشيحthe residue was filtered through silica gel with n-heptane

الإجراء التجريبي

200 g (0.665 mol) of 1-bromo-3-fluoro-4-iodobenzene were dissolved in 800 ml of tetrahydrofuran, and 440 ml (0.698 mmol) of a 15 percent solution of n-butyllithium in hexane were added dropwise at −70° C. After 30 minutes, a solution of 117 g (0.698 mol) of 4-pentylcyclohexanone in 200 ml of tetrahydrofuran was added, and the batch was left to stirr for 60 minutes, hydrolysed using water and acidified using conc. hydrochloric acid. The organic phase was separated off, washed with water and dried over sodium sulfate, and the solvent was removed under reduced pressure. The crude product was subsequently dissolved in 1.4 l of toluene and, after addition of 6 g of toluenesulfonic acid, heated on a water separator until water of reaction was no longer separated off. The solution was washed with water and evaporated, and the residue was filtered through silica gel with n-heptane, giving 124 g (58%) of 4-bromo-2-fluoro-1-(4-pentylcyclohex-1-enyl)benzene as a yellow oil.

المصدر