Reaktion #410364

Reaktionsgleichung

2-chloro-1H-benzimidazole

tetrahydrofuran

2-chloroethyl ethyl ether

potassium bis(trimethylsilyl)amide

→

1-(2-ethoxyethyl)-2-chloro-1H-benzimidazole

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONAdd dropwise
2. 2
   TemperaturWarm to ambient temperature
3. 3
   Temperaturheat to reflux
4. 4
   workup.WAITAfter 12 hours
5. 5
   Temperaturcool to ambient temperature
6. 6
   SonstigeSeparate the organic layer
7. 7
   Extraktionextract the aqueous layer with dichloromethane
8. 8
   TrocknenDry the combined organic layers over Na2SO4
9. 9
   Filtrationfilter
10. 10
    Sonstigeevaporate in vacuo

Vorschrift

Combine 2-chloro-1H-benzimidazole (15.3 g, 100 mmol) and tetrahydrofuran (300 mL). Cool to −70° C. Add dropwise, a solution of potassium bis(trimethylsilyl)amide (200 mL, 0.5 M in toluene, 100 mmol). After 30 minutes, add 2-chloroethyl ethyl ether (22.2 g, 200 mmol) and tetrabutylammonium bromide (0.5 g). Warm to ambient temperature and heat to reflux. After 12 hours, cool to ambient temperature and add water. Separate the organic layer and extract the aqueous layer with dichloromethane. Dry the combined organic layers over Na2SO4, filter, and evaporate in vacuo to give 1-(2-ethoxyethyl)-2-chloro-1H-benzimidazole.

Quelle