Reaktion #8208

Reaktionsgleichung

2-bromo-4,6-difluoro-N-carbethoxy aniline

triethyl amine

Trimethylsilyl acetylene

→

2-(trimethylsilylethynyl)-4,6-difluoro-N-carbethoxyaniline

Ausbeute 71.0%

Lösungsmittel

CH3CN

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigepurged with N2
2. 2
   workup.ADDITIONare added
3. 3
   Waschenrinsed in with 100 mL of CH3CN
4. 4
   Sonstigereaction
5. 5
   Temperaturis refluxed under N2
6. 6
   SonstigeApproximately 2 hours later, the starting material is consumed
7. 7
   TemperaturThe reaction is cooled
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated
10. 10
    workup.DISSOLUTIONthe residue is dissolved in ethyl acetate
11. 11
    Waschenwashed with H2O, brine
12. 12
    Trocknendried (Na2SO4)
13. 13
    Filtrationfiltered
14. 14
    Einengenconcentrated
15. 15
    Sonstigeis purified by flash chromatography (SiO2, ethyl acetate/hexane gradient)

Vorschrift

In a 2 L flask, 2-bromo-4,6-difluoro-N-carbethoxy aniline (42 g, 150 mmol) in CH3CN (500 mL) is degassed with vacuum and purged with N2. Dichlorobis(triphenylphosphine)palladium(II) (10.5 g, 15 mmol, 10 mol %), followed by CuI (710 mg, 4 mmol, 2.5 mol %) and triethyl amine (41 mL) are added and rinsed in with 100 mL of CH3CN. Trimethylsilyl acetylene (31.8 ml, 225 mmol) is added and reaction is refluxed under N2. Approximately 2 hours later, the starting material is consumed, indicated by TLC (20% ethyl acetate/hexane, UV). The reaction is cooled, filtered, concentrated, and the residue is dissolved in ethyl acetate, washed with H2O, brine, dried (Na2SO4), filtered, concentrated, and is purified by flash chromatography (SiO2, ethyl acetate/hexane gradient) to yield 30 g of 2-(trimethylsilylethynyl)-4,6-difluoro-N-carbethoxyaniline (71%).

Quelle