Réaction #8644

Équation de réaction

hexabromospirobifluorene

biphenylboronic acid

→

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

Solvants

toluene

toluene

potassium carbonate

Conditions de réaction

Traitement

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

Mode opératoire

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.

Source