Step 2: 6-Bromo-4-azaindole (1.0 g, 5 mmol) was dissolved in N,N-dimethylformamide (10 mL) and cooled in an ice bath. Sodium hydride (400 mg, 10 mmol, 60% dispersed in mineral oil) was added slowly with stirring. The ice bath temperature was maintained and stirring was continued for 1 hour. Subsequently, iodomethane (852 mg, 6 mmol) was added dropwise and the reaction mixture was warmed to 25 °C and stirred for 2 hours. Upon completion of the reaction, the reaction was quenched with methanol. The mixture was concentrated to dryness under reduced pressure. The residue was purified by column chromatography (silica gel, 100-200 mesh, eluent: hexane solution of 20% ethyl acetate) to afford 6-bromo-1-methyl-1H-pyrrolo[3,2-b]pyridine (1 g, 95% yield).1H NMR (400 MHz, chloroform-d) δ 8.47 (d, J=2 Hz, 1H), 7.75-7.74 (m, 1H) , 7.25-7.23 (m, 1H), 6.65-6.63 (m, 1H), 3.76 (s, 3H).