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5-Methyl-1-triisopropylsilyl-1H-pyrrolo[2,3-b]pyridine (8, 1 g, 2.0 mmol) was used as a starting material and dissolved in 10 mL of tetrahydrofuran. In another vessel, iodine (0.43 g, 1.7 mmol) was dissolved in 5 mL of tetrahydrofuran, which was subsequently added to the tetrahydrofuran solution of the starting material. The reaction mixture was stirred overnight at room temperature. Upon completion of the reaction, the reaction was quenched with 20 mL of aqueous 1 M sodium thiosulfate, followed by extraction with ethyl acetate. The organic layers were combined, washed sequentially with water and brine, and then dried over anhydrous sodium sulfate. The dried organic phase was filtered and the filtrate was concentrated under vacuum. The resulting crude product was purified by silica gel column chromatography using ethyl acetate and hexane as eluents. The grades containing the target product were collected, combined and concentrated under vacuum to afford 3-iodo-5-methyl-1H-pyrrolo[2,3-b]pyridine (10, 20 mg) as a white solid. The mass spectrum (ESI) showed [M + H]+ = 258.70.

[1] Patent: US2011/263595, 2011, A1. Location in patent: Page/Page column 78-79
[2] Patent: US9096593, 2015, B2. Location in patent: Page/Page column 90; 91