Sodium Thiosulfate → 2-(2,6-Dichloro-4-fluorophenyl)-2H-pyrazolo[4,3-c]pyridine-5-oxide

Participants

Reaction Conditions

Reaction Steps

To a cooled (0° C.) solution of 2-(2,6-dichloro-4-fluorophenyl)-2H-pyrazolo[4,3-c]pyridine (1.6 g, 5.67 mmol) in DCM (30 mL) under nitrogen, was added mCPBA (1.47 g, 8.51 mmol). The reaction mixture was stirred at 0° C. for 2 hours, warmed to room temperature, and stirred for a further 16 hours. Sodium thiosulfate (sat. aq.) was added and the organic layer was separated, washed with sodium hydrogen carbonate (sat. aq.) and brine, dried over anhydrous magnesium sulfate, and concentrated to dryness under reduced pressure. The residue was purified by silica gel flash chromatography (5-10% methanol in DCM) to afford the title compound as a white solid (1.4 g, 83% yield). 1H NMR (300 MHz, DMSO-d6): δ 8.90 (s, 1H), 8.82 (s, 1H), 7.98-7.87 (m, 3H), 7.83 (d, J=7.5 Hz, 1H).

Provenance & Evidence