Under a nitrogen atmosphere, tert-butyl3-{[4-chloro-3-(3-chloro-5-cyanophenoxy)-5-fluorophenoxy]methyl}-6-fluoro-1H-pyrazolo[3,4-b]pyridine-1-carboxylate (50-6) (230 mg, 0.420 mmol) was dissolved in NMP (4 mL, 0.1 M). Next, 4-methoxybenzylamine (288 mg, 2.101 mmol) was added and the reaction was heated to 95° C. for 2 hours. It was then diluted with EtOAc (4 mL). It was partitioned with water (3 mL) and then extracted with EtOAc (3×4 mL). The organic extracts were then washed with water (3×4 mL) and brine (1×4 mL), dried over sodium sulfate and concentrated. The crude reaction material was then diluted with TFA (3 mL) and heated to 65° C. for 2 hours. It was then concentrated and purified on a reverse phase system (5%-95% AcCN/H2O with 0.5% TFA) to give 3-{5-[(6-amino-1H-pyrazolo[3,4-b]pyridin-3-yl)methoxy]-2-chloro-3-fluorophenoxy}-5-chlorobenzonitrile (50-7) (8 mg, 4%). LCMS (ES) m/z 445.9 (M+).
