A mixture of 3,5-dichloro-4-(4-chloro-pyrazolo[4,3-c]pyridin-2-yl)-benzonitrile (3.23 g, 10 mmol), tert-butyl carbamate (5.85 mg, 50 mmol), Pd2(dba)3 (458 mg, 0.5 mmol), Xantphos (576 mg, 1.0 mmol) and potassium phosphate tribasic (4.24 g, 20 mmol) in toluene (100 mL) and water (20 mL) was degassed with argon then heated at 90° C. for 30 minutes. The reaction was cooled to room temperature and then filtered through Celite® using ethyl acetate to wash the filter pad. The filtrate was washed with water and sodium bicarbonate (sat. aq.), dried over sodium sulfate and concentrated under reduced pressure. The resultant residue was purified by silica gel flash chromatography (0-50% ethyl acetate in cyclohexane) to afford the title compound as an off-white solid (5.0 g, contaminated with residual tert-butyl carbamate). LCMS (Method D): RT=2.44 min, m/z: 348 [M−C4H7+].
