Diacetoxypalladium (6.90 mg, 0.031 mmol) and 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (77 mg, 0.123 mmol) were combined in toluene (4 mL) and the solution was stirred at 40° C. for 10 minutes. A mixture of 7-iodo-1-(4-methoxybenzyl)-1H-pyrazolo[4,3-b]pyridine and 7-iodo-1-(4-methoxybenzyl)-2H-pyrazolo[4,3-b]pyridine (290 mg, 0.794 mmol) in toluene (4 mL), 6-(2,5-difluorophenyl)-2,3-dimethylpyridin-4-amine (72 mg, 0.307 mmol) and sodium 2-methylpropan-2-olate (29.5 mg, 0.307 mmol) were added. The reaction mixture was heated at 100° C. for 20 hours. A further 0.2 eq of diacetoxypalladium, 0.4 eq of 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl and 2 eq of sodium 2-methylpropan-2-olate were added and the reaction heated at 100° C. for 12 hours. The solvent was then evaporated in vacuo to give a residue which was purified via preparative HPLC using a gradient of 5-30% acetonitrile (containing 0.035% TFA) in water (containing 0.05% TFA) using a Sunfire Prep 5 μm C18, 75×30 mm column to give N-(6-(2,5-difluorophenyl)-2,3-dimethylpyridin-4-yl)-1-(4-methoxybenzyl)-2H-pyrazolo[4,3-b]pyridin-7-amine and N-(6-(2,5-difluorophenyl)-2,3-dimethylpyridin-4-yl)-2-(4-methoxybenzyl)-2H-pyrazol[4,3-b]pyridin-7-amine which was used without further purification.
