A suspension of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-trityl-1H-pyrazolo[3,4-b]pyridine (307 mg, 0.630 mmol), 2-(3-bromophenyl)-2-methylbutanenitrile (150 mg, 0.630 mmol) and 2 M aqueous solution of sodium carbonate (0.945 ml, 1.89 mmol) in dioxane (4 ml) was degassed by vacuum/nitrogen cycles (×5). Bis(tri-tert-butylphosphine)palladium(0) (16.10 mg, 0.032 mmol) was added and the resultant mixture was degassed by vacuum/nitrogen cycles (×5) and stirred at room temperature for 18 hours. The mixture was partitioned between ethyl acetate and a saturated aqueous solution of sodium carbonate. The organic phase was dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was purified on silica gel by flash column chromatography to afford the title compound as a sticky white solid (0.240 mg, 80% purity, 59% yield).
