General procedure for the synthesis of 5-bromo-3-fluoro-1H-pyrrolo[2,3-b]pyridines from 5-bromo-7-azaindoles: first, 3-fluoro-1H-pyrrolo[2,3-b]pyridin-5-ylboronic acid (67) was prepared. Compound 65 (4 g, 20 mmol) was dissolved in a mixed solution of acetonitrile (500 mL) and acetic acid (100 mL), followed by the addition of Select-Fluor (10 g, 30 mmol). The reaction mixture was heated and reacted at 80°C overnight. The progress of the reaction was monitored by thin layer chromatography (TLC, unfolding agent was petroleum ether/ethyl acetate, 5:1, v/v) to confirm complete consumption of compound 65. Upon completion of the reaction, the mixture was concentrated under reduced pressure and the residue was purified by silica gel fast column chromatography (eluent was petroleum ether/ethyl acetate, 10:1, v/v) to afford compound 66 (0.64 g, 13% yield) as an off-white solid.1H NMR (400 MHz, CDCl3): δ 9.434 (brs, 1H), 8.311-8.280 (m , 1H), 8.056-8.023 (m, 1H), 7.191 (s, 1H), 7.086-7.053 (m, 1H).
![1H-Pyrrolo[2,3-b]pyridine, 5-broMo-3-fluoro-](/CAS/GIF/1111637-68-3.gif)