Reaktion #8644

Reaktionsgleichung

hexabromospirobifluorene

biphenylboronic acid

→

2,2′,4,4′,7,7′-hexabiphenylyl-9,9′-spirobifluorene

Lösungsmittel

toluene

toluene

potassium carbonate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeIn a 250 ml two-necked flask fitted
2. 2
   Temperaturwith reflux condenser and precision glass stirrer
3. 3
   TemperaturThe mixture is refluxed under nitrogen
4. 4
   Temperaturunder reflux for 7 hours
5. 5
   Filtrationthe cooled solution is filtered
6. 6
   Extraktionthe filtrate is extracted twice
7. 7
   workup.STIRRINGby shaking with water (
8. 8
   Sonstigethe phase separation, chloroform
9. 9
   workup.ADDITIONis added)
10. 10
    TrocknenThe organic phase is dried over sodium sulfate
11. 11
    Filtrationfiltered through a short column of silica gel
12. 12
    Sonstigesubsequently evaporated on a rotary evaporator
13. 13
    SonstigeThe product is further purified by recrystallization from dichloromethane/pentane

Vorschrift

In a 250 ml two-necked flask fitted with reflux condenser and precision glass stirrer, 1.6 g of hexabromospirobifluorene and 3 g of biphenylboronic acid are slurried in a mixture of 50 ml of toluene and 50 ml of 1 M potassium carbonate solution. The mixture is refluxed under nitrogen and 115 mg of tetrakis(triphenylphosphine)palladium in 5 ml of toluene are added. The mixture is boiled under reflux for 7 hours while stirring. After the reaction is complete, the cooled solution is filtered and the filtrate is extracted twice by shaking with water (to improve the phase separation, chloroform is added). The organic phase is dried over sodium sulfate, filtered through a short column of silica gel and subsequently evaporated on a rotary evaporator. The product is further purified by recrystallization from dichloromethane/pentane. This gives 2 g (80%) of colorless crystals which fluoresce blue under UV illumination.

Quelle