5-Bromoindole → 5-Bromo-1-(triisopropylsilyl)-1H-indole

Temperature

-78 °C

Lithium bis(trimethylsilyl)amide (1.0 M in THF, 28 mL, 28 mmol) was slowly added to a solution of 5-bromoindole (5.00 g, 25.5 mmol) in THF (60 mL) at −78° C., under nitrogen atmosphere. The reaction mixture was stirred at −78° C. for 20 minutes, then triisopropylsilylchloride (5.7 mL, 26.8 mmol) was added. The resulting mixture was stirred at −78° C. for 20 minutes, then warmed to room temperature over a period of 1 hour. The reaction was quenched by addition of a saturated aqueous solution of NH4Cl, diluted with water, and the resulting mixture was extracted with EtOAc. The organic layer was separated, dried over MgSO4, filtered and evaporated under reduced pressure to give a crude oil that was purified by flash chromatography (hexane 100%) providing 8.94 g (99% yield) of 5-bromo-1-triisopropylsilanyl-1H-indole as a colorless oil.

1. stirringThe resulting mixture was stirred at −78° C. for 20 minutes
2. temperaturewarmed to room temperature over a period of 1 hour
3. customThe reaction was quenched by addition of a saturated aqueous solution of NH4Cl
4. additiondiluted with water
5. extractionthe resulting mixture was extracted with EtOAc
6. customThe organic layer was separated
7. dry with materialdried over MgSO4
8. filtrationfiltered
9. customevaporated under reduced pressure
10. customto give a crude oil that
11. customwas purified by flash chromatography (hexane 100%)

ORD record

ord-0308d713f8e34779b2b3a671c0a56579

Source dataset

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08084623B2