Reaction #7057

Reaction equation

n-BuLi

3-methoxythiophene

Chlorotrimethylsilane

→

title compound

Yield 82.0%

2-Trimethylsilyl-3-methoxythiophene

Yield 82.0%

Solvents

Et2O

Conditions

Workup

1. 1
   TemperatureThe mixture is warmed to room temperature
2. 2
   workup.STIRRINGstirred for 3 hr
3. 3
   OtherThe reaction is quenched with water (50 mL) and hexanes (100 mL)
4. 4
   ExtractionThe aqueous layer is extracted with hexanes (50 mL)
5. 5
   DryingThe combined organic extracts are dried (Na2SO4)
6. 6
   Filtrationfiltered
7. 7
   Concentrationconcentrated
8. 8
   OtherThe crude product is chromatographed on silica gel
9. 9
   Washeluting with hexanes

Procedure

A solution of n-BuLi (19.7 mL of 1.6 M in hexanes, 31.5 mmol) is added dropwise to a solution of 3-methoxythiophene (3.0 g, 26.3 mmol) in anhydrous Et2O (20 mL) under nitrogen at −70° C. The mixture is stirred at −70° C. for 2 hr. Chlorotrimethylsilane (4.5 mL, 35.4 mmol) is added slowly to the solution. The mixture is warmed to room temperature and stirred for 3 hr. The reaction is quenched with water (50 mL) and hexanes (100 mL). The aqueous layer is extracted with hexanes (50 mL). The combined organic extracts are dried (Na2SO4), filtered and concentrated. The crude product is chromatographed on silica gel, eluting with hexanes to afford the title compound (4.0 g, 82%) as a colorless liquid.

Source