Reaction #2697

Reaction equation

2,2,6,6-tetramethylbenzo[1,2-d:5,4-d']-bis(1,3)oxathiole

n-butyllithium

chlorotrimethylsilane

→

8-Trimethylsilyl-2,2,6,6-tetramethylbenzo[1,2-d:5,4-d']-bis(1,3)oxathiole

Solvents

THF

Conditions

Workup

1. 1
   Otherusing deoxygenated solvents
2. 2
   TemperatureThe mixture was cooled on an ice-bath
3. 3
   workup.WAITAfter another 15 min
4. 4
   Otherthe reaction mixture was quenched with dietyl ether/aq
5. 5
   ExtractionNaHCO3, the aqueous layer was extracted with ether
6. 6
   Washthe combined organic layers were washed with water
7. 7
   Dryingdried (Na2SO4)
8. 8
   OtherAfter evaporation and chromatography (silica gel, chloroform) essentially pure product (6.3 g, 92%)
9. 9
   Othercould be collected

Procedure

The reaction was performed under an argon atmosphere using deoxygenated solvents. 2,2,6,6-tetramethylbenzo[1,2-d:5,4-d']-bis(1,3)oxathiole (6.0 g, 23.6 mmol) was dissolved in dry THF (120 mL). The mixture was cooled on an ice-bath and n-butyllithium (10.8 mL, 2.5M in hexane) was added dropwise over 10 min. After 15 min, chlorotrimethylsilane (6.0 mL, 47.2 mmol) was added dropwise over 5 min. After another 15 min, the reaction mixture was quenched with dietyl ether/aq. NaHCO3, the aqueous layer was extracted with ether and the combined organic layers were washed with water and dried (Na2SO4). After evaporation and chromatography (silica gel, chloroform) essentially pure product (6.3 g, 92%) could be collected.

Source