Reaction #1885004

Reaction equation

o-tolylboronic acid

2,5-dibromonitrobenzene

potassium carbonate

→

2,2″-dimethyl-2′-nitro-p-terphenyl

Solvents

water

THF

Conditions

Workup

1. 1
   Otherdegassed
2. 2
   Temperaturethe mixture is heated
3. 3
   Temperatureunder reflux for 20 h
4. 4
   TemperatureAfter cooling
5. 5
   Otherthe organic phase is separated off
6. 6
   Washwashed three times with 200 ml of water
7. 7
   Dryingonce with 200 ml of saturated, aqueous sodium chloride solution, dried over magnesium sulfate
8. 8
   Otherevaporated to dryness in vacuo in a rotary evaporator
9. 9
   OtherThe grey residue is recrystallised from hexane
10. 10
    FiltrationThe deposited crystals are filtered off with suction
11. 11
    Washwashed with a little MeOH
12. 12
    Otherdried in vacuo

Procedure

5.46 g (4.7 mmol) of Pd(PPh3)4 are added to a well-stirred, degassed suspension of 155 g (1140 mmol) of o-tolylboronic acid, 133.4 g (474.9 mmol) of 2,5-dibromonitrobenzene and 305.3 g (1435 mmol) of potassium carbonate in a mixture of 250 ml of water and 250 ml of THF, and the mixture is heated under reflux for 20 h. After cooling, the organic phase is separated off, washed three times with 200 ml of water and once with 200 ml of saturated, aqueous sodium chloride solution, dried over magnesium sulfate and evaporated to dryness in vacuo in a rotary evaporator. The grey residue is recrystallised from hexane. The deposited crystals are filtered off with suction, washed with a little MeOH and dried in vacuo; yield: 50.5 g, 97% of theory; purity: 99.2% according to HPLC.

Source