Reaction #44599

Reaction equation

cesium fluoride

dioxane

1-bromo-3,4,5-trifluorobenzene

trans-1-propen-1-ylboronic acid

→

title compound

Yield 84.1%

1,2,3-trifluoro-5-((E)-propenyl)benzene

Yield 84.1%

Solvents

water

hexane

water

Conditions

Workup

1. 1
   OtherThe resulting reaction solution
2. 2
   Temperaturecooled to room temperature
3. 3
   OtherThe precipitated insoluble matter was removed by filtration
4. 4
   Otherthe organic layer was separated
5. 5
   WashThe obtained organic layer was washed with water
6. 6
   Otherthe insoluble matter was removed by filtration again
7. 7
   OtherThe organic layer was separated
8. 8
   WashThe obtained organic layer was washed with water
9. 9
   Dryingwith saturated saline, dried over anhydrous magnesium sulfate
10. 10
    Concentrationconcentrated under reduced pressure
11. 11
    OtherThe residue was purified by silica gel column chromatography (eluting solvent: hexane)

Procedure

In nitrogen atmosphere, tetrakistriphenyl-phosphine palladium(0) (4.66 g) and cesium fluoride (21.4 g) were added to a solution mixture of dioxane (95 mL) and water (5 mL) of 1-bromo-3,4,5-trifluorobenzene (8.5 g), trans-1-propen-1-ylboronic acid (4.1 g). The resulting reaction solution was stirred at 80° C. for 5 hr and cooled to room temperature. To the reaction solution, hexane and water were added. The precipitated insoluble matter was removed by filtration, and the organic layer was separated. The obtained organic layer was washed with water, and the insoluble matter was removed by filtration again. The organic layer was separated. The obtained organic layer was washed with water and then with saturated saline, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting solvent: hexane) to give 5.83 g of the title compound. The physical property values of this compound were as follows:

Source