Reaktion #324763

Reaktionsgleichung

1,4-dioxane

2,5-dibromo-1,3-dimethylbenzene

Na2CO3

→

title compound

3-(4-Bromo-3,5-dimethylphenyl)furan

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeis purged with argon for 5 min
2. 2
   workup.ADDITIONTetrakis-triphenylphosphine-palladium-(0) (270 mg) is added
3. 3
   workup.ADDITIONMore tetrakis-triphenylphosphine-palladium-(0) (50 mg) is added
4. 4
   workup.STIRRINGthe mixture is stirred for another 5 h at 100° C
5. 5
   TemperaturAfter cooling to room temperature the mixture
6. 6
   workup.ADDITIONis diluted with ethyl acetate and aqueous NH4Cl solution
7. 7
   ExtraktionThe aqueous phase is extracted with ethyl acetate
8. 8
   Waschenthe combined extracts are washed with brine
9. 9
   Trocknendried over MgSO4
10. 10
    Einengenconcentrated in vacuo
11. 11
    SonstigeThe residue is chromatographed on silica gel (cyclohexane/ethyl acetate 100:0→90:10)

Vorschrift

A mixture of 2,5-dibromo-1,3-dimethylbenzene (2.00 g), 1-furan-3-ylboronic acid (856 mg), and 2 M aqueous Na2CO3 solution (11 mL) in 1,4-dioxane (40 mL) is purged with argon for 5 min. Tetrakis-triphenylphosphine-palladium-(0) (270 mg) is added and the mixture is stirred at 100° C. over night. More tetrakis-triphenylphosphine-palladium-(0) (50 mg) is added and the mixture is stirred for another 5 h at 100° C. After cooling to room temperature the mixture is diluted with ethyl acetate and aqueous NH4Cl solution. The aqueous phase is extracted with ethyl acetate and the combined extracts are washed with brine, dried over MgSO4 and concentrated in vacuo. The residue is chromatographed on silica gel (cyclohexane/ethyl acetate 100:0→90:10) to give the title compound. LC (method 7): tR=1.22 min; Mass spectrum (EI+): m/z=250 [M]+.

Quelle