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General procedure for the synthesis of methyl 3-iodoindazole-6-carboxylate from methyl 1H-indazole-6-carboxylate: To a solution of methyl 1H-indazole-6-carboxylate (2.5 g, 14.2 mmol) in DMF (30 mL) was added in batches of KOH (1.8 g, 31.9 mmol), followed by the addition of iodine (5.4 g, 21.3 mmol) at 0 °C. The reaction mixture was stirred at room temperature for 1 hour. After completion of the reaction, the mixture was poured into ice water and extracted twice with EtOAc. The organic phases were combined, washed sequentially with 5% Na2S2O4 aqueous solution and brine, dried and concentrated to dryness to afford methyl 3-iodoindazole-6-carboxylate (4.0 g, 93.3% yield) as a yellow solid, which could be used in the next reaction without further purification.LC/MS (ESI) m/z: 303 (M + H)+.

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