Reaktion #2021944

Reaktionsgleichung

water

magnesium

1,4-cyclohexandione monoethylene ketal

4-tert-butyl-1-bromobenzene

→

8-[4-(tert-butyl)phenyl]-1,4-dioxaspiro[4.5]decan-8-ol

Lösungsmittel

acetic acid

tetrahydrofuran

ethyl ether

ethyl ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturWhile refluxing the suspension
2. 2
   Temperaturunder reflux for one hour
3. 3
   Sonstigewas elevated to ambient temperature
4. 4
   workup.STIRRINGAfter stirring the mixture at the same temperature as above, the reaction mixture
5. 5
   workup.STIRRINGstirred at ambient temperature for 20 minutes
6. 6
   Extraktionextracted with ethyl acetate
7. 7
   WaschenThe organic layer was washed successively with water and saturated aqueous solution of sodium chloride
8. 8
   Trocknendried over anhydrous magnesium sulfate
9. 9
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure
10. 10
    SonstigePurification of the residue by column chromatography [eluent: hexane:ethyl acetate=3:1]

Vorschrift

In an atmosphere of nitrogen, 0.23 g of magnesium powder was suspended in 2 ml of anhydrous ethyl ether. While refluxing the suspension, a solution of 2.00 g of 4-tert-butyl-1-bromobenzene in 10 ml anhydrous ethyl ether was dropwise added. After stirring the resulting mixture under reflux for one hour, a solution of 1.17 g of 1,4-cyclohexandione monoethylene ketal in 10 ml anhydrous tetrahydrofuran was dropwise added at 0-5° C., and the temperature was elevated to ambient temperature. After stirring the mixture at the same temperature as above, the reaction mixture was poured into a mixture of water and acetic acid, stirred at ambient temperature for 20 minutes, and extracted with ethyl acetate. The organic layer was washed successively with water and saturated aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure. Purification of the residue by column chromatography [eluent: hexane:ethyl acetate=3:1] gave 1.25 of 8-[4-(tert-butyl)phenyl]-1,4-dioxaspiro[4.5]decan-8-ol as a light yellow oily product.

Quelle