Reaction #75456

Reaction equation

4,4′-diiodobiphenyl

3,5-di-α-naphthyl bromobenzene

magnesium

1,2-dibromoethane

→

solid

Yield 81.0%

3,3″,5,5″-tetra-naphthyl-p-quaterphenyl

Yield 81.0%

Solvents

THF

THF

THF

THF

Conditions

Workup

1. 1
   workup.ADDITIONAfter the addition
2. 2
   Temperaturethe brown solution was heated
3. 3
   Temperatureat reflux for 2 hrs
4. 4
   Temperatureand then cooled to room temperature
5. 5
   workup.ADDITIONwas then added
6. 6
   Otheran orange solution resulted
7. 7
   TemperatureHeat
8. 8
   TemperatureThe mixture was then heated
9. 9
   Temperatureat reflux for 45 min.
10. 10
    Temperaturecooled to room temperature during which time a solid
11. 11
    Otherprecipitated out of solution
12. 12
    workup.ADDITIONA 2.0 M solution of HCl was added to the mixture
13. 13
    Otherthe water layer was removed
14. 14
    FiltrationThe solid precipitate was collected by filtration
15. 15
    Washwashed with water and diethyl ether

Procedure

A solution of 3,5-di-α-naphthyl bromobenzene (10.0 g, 0.0244 mol) in anhydrous THF (70 mL) was added dropwise to magnesium turnings (0.59 g, 0.0244 mol) in 10 mL THF. The solution was heated at 60° C. during the addition and the reaction was initiated using 1,2-dibromoethane. After the addition was complete, the brown solution was heated at reflux for 2 hrs. and then cooled to room temperature. In a separate flask, 4,4′-diiodobiphenyl (3.3 g 0.008 mol) and 0.3 g of dichlorobis(triphenyl phosphine)palladium(II) were placed under nitrogen and 30 mL of anhydrous THF was added. The Grignard reagent prepared about THF solution was then added using needle-transfer and an orange solution resulted. Heat was applied and the solution turned to almost black. The mixture was then heated at reflux for 45 min. and cooled to room temperature during which time a solid precipitated out of solution. A 2.0 M solution of HCl was added to the mixture and after stirring for 30 minutes, the water layer was removed. The solid precipitate was collected by filtration and washed with water and diethyl ether to yield a white solid (5.3 g, 81%)

Source