Реакция #1277

Уравнение реакции

3,4-difluorobromobenzene

water

4-(4-propylcyclohexyl)-phenyltrimethoxysilane

TBAF

→

white crystals

Выход 94.5%

4-(4-propylcyclohexyl)-3',4'-difluorobiphenyl

Выход 94.5%

Растворители

toluene

toluene

toluene

Условия реакции

Обработка

1. 1
   ДругоеAfter the solvent was removed under reduced pressure
2. 2
   ТемператураThe resulting mixture was refluxed for 3 hours
3. 3
   ТемператураAfter cooling, to the reaction mixture
4. 4
   ДругоеThe organic layer was separated
5. 5
   Экстракцияthe aqueous layer was extracted with toluene three times
6. 6
   СушкаThe combined organic layer was dried over magnesium sulfate
7. 7
   ДругоеAfter the magnesium sulfate was removed by filtration
8. 8
   Другоеthe filtrate was evaporated under reduced pressure
9. 9
   ДругоеThe residue was purified by silica gel column chromatography (heptane)

Методика

To 0.645 g (2 mmol) of 4-(4-propylcyclohexyl)-phenyltrimethoxysilane (Ih) was added 2.1 ml of TBAF (2.1 mmol, 1M in THF) under nitrogen, and the mixture was stirred at room temperature for 30 minutes. After the solvent was removed under reduced pressure, a solution of 3,4-difluorobromobenzene (0.463 g, 2.4 mmol) in toluene (1 ml) was added, followed by the addition of a suspension of tetrakis(triphenylphosphine)palladium(0) (0.116 g, 0.1 mmol) in toluene (3 ml). The resulting mixture was refluxed for 3 hours. After cooling, to the reaction mixture were added water and toluene. The organic layer was separated and the aqueous layer was extracted with toluene three times. The combined organic layer was dried over magnesium sulfate. After the magnesium sulfate was removed by filtration, the filtrate was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (heptane) to obtain 0.594 g (40%) of white crystals.

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