To a stirred solution of N-(4-(hydroxymethyl)-2-iodo-5-(methylthio)phenyl)methanesulfonamide (6.4 g, 17.2 mmol) and imidazole (1.76 g, 25.8 mmol) in CH2Cl2 (100 mL) and DMF (50 mL) at 0° C. was added tert-butyldiphenylsilyl chloride (5.8 mL, 22.4 mmol). The mixture was allowed to stir at rt overnight. The mixture was diluted with CH2Cl2 (100 mL), washed with 1N HCl solution, sat. aq. NaHCO3 and brine, dried over anhydrous Na2SO4, filtered and concentrated in vacuo to afford N-(4-(((tert-butyldiphenylsilyl)oxy)methyl)-2-iodo-5-(methylthio)phenyl)methanesulfonamide. It was used for next step without further purification.
