Reaktion #1063743

Reaktionsgleichung

indole

2-Bromobenzonitrile

sec-Butyllithium

5-bromo-1-triisopropylsilylindole

triphenylphosphine

→

5-(2-cyanophenyl)-1-triisopropylsilylindole

Ausbeute 52.4%

Lösungsmittel

THF

THF

brine

ether

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGstirred for 40 minutes
2. 2
   Temperaturcooled to -78° C
3. 3
   workup.STIRRINGThe solution was stirred for 10 minutes
4. 4
   workup.STIRRINGAfter stirring for 5 minutes
5. 5
   Temperaturto warm to room temperature
6. 6
   workup.STIRRINGstirred for 2 hours
7. 7
   TrocknenThe organic phase was dried over magnesium sulfate
8. 8
   Einengenconcentrated in vacuo
9. 9
   SonstigeThe product was chromatographed over silica gel
10. 10
    Wascheneluted with 0-15% ether in hexane

Vorschrift

sec-Butyllithium (41 mmole, 31.5 ml) was added dropwise over 10 minutes to 5-bromo-1-triisopropylsilylindole (40 mmoles, 14.0 g) in 400 ml THF at -78° C. The solution was stirred for 15 minutes. A solution of anhydrous ZnCl2 in 50 ml THF was added. The solution was warmed to 0° C. and stirred for 40 minutes. In a separate flask nickel acetylacetonate (1.5 mmole, 0.385 g) and triphenylphosphine (6.0 mmoles, 1.60 g) were dissolved in 20 ml of THF and cooled to -78° C. DIBAL (1.5 mmole, 1.5 ml of 1.0M solution in hexane) was added. The solution was stirred for 10 minutes. 2-Bromobenzonitrile (39.9 mmoles, 7.26 g) was added. After stirring for 5 minutes, the indole solution was added over a 10 minute period. The mixture was allowed to warm to room temperature, stirred for 2 hours, and then added to ether and brine. The organic phase was dried over magnesium sulfate and concentrated in vacuo. The product was chromatographed over silica gel eluted with 0-15% ether in hexane to yield 7.83 g of 5-(2-cyanophenyl)-1-triisopropylsilylindole. (MS)

Quelle