1-(3-bromo-2-methylphenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-ol (Intermediate AT4) (2 g, 6.55 mmol) and Zinc cyanide (0.693 g, 5.90 mmol) were dissolved in DMF (30 mL)and sealed into a microwave tube. The tube was purged with nitrogen. 9,9-Dimethyl-4,5-bis(diphenylphosphino)xanthene (0.379 g, 0.66 mmol) and tris(dibenzylideneacetone)dipalladium(0) (0.300 g, 0.33 mmol) added. The reaction was heated to 160° C. for 10 minutes in the microwave reactor and cooled to RT. The reaction mixture was filtered and the solid washed with DMF (until the filtrate was colourless) to afford the product (1.340 g, 81%) which was used without further purification. 1H NMR (400 MHz, DMSO) δ 2.19 (3H, s), 7.54 (1H, t), 7.71 (1H, d), 7.94 (1H, d), 8.02 (1H, s), 8.30 (1H, s), 12.32 (1H, s)
