Reaktion #157907

Reaktionsgleichung

Phenylmagnesium chloride

HCl

Mesitylmagnesium bromide

cycloheptanone

diphenyl chlorophosphate

→

1-phenylcycloheptene

Ausbeute 43.0%

Lösungsmittel

pentane

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeto reach room temperature
2. 2
   workup.STIRRINGAfter stirring the solution for 30 min
3. 3
   Temperaturthe solution was warmed to 65° C
4. 4
   Sonstigeresulting in
5. 5
   Temperatura gentle reflux of the solvent
6. 6
   workup.STIRRINGAfter stirring at 65° C. for 30 minutes
7. 7
   Temperaturthe mixture was cooled to rt
8. 8
   SonstigeThe phases were separated
9. 9
   Extraktionthe aqueous portion was extracted with pentane (30 mL)
10. 10
    WaschenThe combined organic phase was washed sequentially with 3 N HCl (20 mL), 3 M NaOH (2×20 mL), and brine (20 mL)
11. 11
    Trocknendried over MgSO4
12. 12
    SonstigeEvaporation of the solvent
13. 13
    workup.DISTILLATIONfollowed by distillation
14. 14
    Sonstigea Kugelrohr apparatus (oven temperature 100-140° C., 0.065 torr)

Vorschrift

Mesitylmagnesium bromide (18.0 mL, 18.0 mmol, 1.0 M in THF) was added over 15 minutes to a solution of cycloheptanone (2.0 g, 17.8 mmol) and diphenyl chlorophosphate (1.1 eq.) in THF (5 mL) at 0° C. The solution was stirred at 0° C. for 30 min, whereafter the solution was allowed to reach room temperature. After stirring the solution for 30 min, dichlorobis(triphenylphosphine)palladium (126 mg, 1 mol %) was added and the solution was warmed to 65° C. Phenylmagnesium chloride (10.8 mL, 1.2 equivalents in THF) was added over 10 minutes, resulting in a gentle reflux of the solvent. After stirring at 65° C. for 30 minutes, the mixture was cooled to rt and poured into a mixture of 3 N HCl (30 mL) and pentane (30 mL). The phases were separated, and the aqueous portion was extracted with pentane (30 mL). The combined organic phase was washed sequentially with 3 N HCl (20 mL), 3 M NaOH (2×20 mL), and brine (20 mL), and dried over MgSO4. Evaporation of the solvent followed by distillation using a Kugelrohr apparatus (oven temperature 100-140° C., 0.065 torr) yielded 1-phenylcycloheptene (1.29 g, 43%).

Quelle