A mixture of tert-butyl 3-{3-[1-(4-amino-3-iodo-1H-pyrazolo[3,4-d]pyrimidin-1-yl)ethyl]-5-chloro-2-ethoxy-6-fluorophenyl}azetidine-1-carboxylate (1.32 g, 2.14 mmol), pyridine-trivinylboroxin (1:1) (0.51 g, 2.1 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II), complex with dichloromethane (1:1) (90 mg, 0.1 mmol) and potassium carbonate (0.89 g, 6.4 mmol) in 1,4-dioxane (10 mL)/water (7 mL) was heated at 100° C. overnight. After cooled to room temperature, the reaction mixture was diluted with water and ethyl acetate. The aqueous layer was extracted with ethyl acetate. The combined extracts were washed with brine, dried over MgSO4, concentrated and purified on a silica gel column to give the desired product (0.71 g, 64%). LCMS calculated for C25H31ClFN6O3 (M+H)+: m/z=517.2; Found:517.2
