N-Fluorobenzenesulfonimide → 4-Fluoro-1-[tris(1-methylethyl)silyl]-1H-pyrrolo[2,3-b]pyridine

Participants

Reaction Steps

4-Bromo-1-(triisopropylsilyl)-1H-pyrrolo[2,3-b]pyridine (50 g, 141.5 mmol) in THF (2 L) at −78° C. was treated dropwise with tert-butyllithium (166.5 mL, 283.0 mmol, 1.7M in pentane). The reaction was then stirred for 15 minutes. N-Fluoro-N-(phenylsulfonyl)benzenesulfonamide (49.08 g, 155.6 mmol) in THF (200 mL) was then added dropwise, and the mixture was stirred at −78° C. After 2 hours, the reaction was quenched at −78° C. with saturated aqueous NH4Cl (200 mL). The aqueous phase was extracted with hexanes. The combined hexane phases were dried (MgSO4) and passed through a plug of silica gel eluting with hexanes. The combined hexanes fractions were concentrated in vacuo to provide 4-fluoro-1-(triisopropylsilyl)-1H-pyrrolo[2,3-b]pyridine (36.1 g, 87% yield) as an oil. 1H NMR (400 MHz, CDCl3) δ □18.18 (dd, 1H), 7.25 (d, 1H), 6.76 (dd, 1H), 1.86-1.81 (m, 3H), 1.13 (d, 18H).

Provenance & Evidence