General procedure for the synthesis of 3-fluoro-2-iodopyridine from 2-chloro-3-fluoropyridine: To a solution of 2-chloro-3-fluoropyridine (400 mg, 3 mmol) in dioxane (6 mL, 0.5 M) was added chlorotrimethylsilane (652 mg, 6 mmol) and sodium iodide (2.20 g, 15 mmol) in one go. The reaction mixture was stirred at 80 °C overnight. After completion of the reaction, the reaction mixture was concentrated to give 660 mg of 3-fluoro-2-iodopyridine (yield: 98%), the product was a yellow oil, which was directly used in the next reaction without further purification.
