To a solution of N-[2-[[(2,3-difluorophenyl)methyl]thio]-6-[(1R)-1-[(4S)-2,2-dimethyl-1,3-dioxolan-4-yl]ethoxy]-4-pyrimidinyl]-1-azetidinesulfonamide (the product of step (0.13 g) in DCM (5 mL) was added iron (III) chloride hexahydrate (0.24 g). The reaction mixture was stirred at ambient temperature for 1 h, then saturated aqueous sodium bicarbonate (10 mL) was added. The layers were separated and the aqueous material extracted with DCM (3×10 mL) and EtOAc (3×10 mL). The combined organic extracts were washed with saturated sodium chloride, dried (MgSO4), filtered and evaporated. The residual pale yellow solid was slowly precipitated from DCM, filtered and the resulting material washed with minimal cold DCM (2×1 mL) to afford the title compound as a white powder. Yield: 45 mg.
