Under argon protection, 4-fluoro-1-(triisopropylsilyl)-1H-pyrrolo[2,3-b]pyridine (3 g, 10 mmol) was dissolved in THF (15 mL) and cooled to 0°C. To this solution was slowly added a THF solution of tetrabutylammonium fluoride (1 M, 10.5 mL). The reaction mixture was gradually warmed to room temperature and stirred continuously for 1 hour. The progress of the reaction was monitored by TLC and after confirming complete consumption of the raw material, the reaction mixture was diluted with water (50 mL) and extracted with ethyl acetate (2 x 100 mL). The organic phases were combined, dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by column chromatography with 20% ethyl acetate/hexane as eluent to afford 4-fluoro-1H-pyrrolo[2,3-b]pyridine (1.3 g, 94% yield) as an off-white solid.1H NMR (CDCl3, 400MHz): δ 10.52 (brs, 1H), 8.30-8.25 (m, 1H), 7.32-7.30 (m , 1H), 6.81 (dd, 1H), 6.59 (s, 1H); TLC: 20% EtOAc/hexane (Rf = 0.2).