To a stirred solution of 5-chloro-N-(3,4-dimethoxyphenyl)thiazolo[5,4-d]pyrimidin-7-amine (150 mg, 0.46 mmol) and (E)-methyl 4-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)styryl)benzoate (200 mg, 0.55 mmol) in 25 mL of 1,4-dioxane were added Na2CO3 (100 mg, 0.94 mmol) and 3 mL of water at room temperature. Then the mixture was degassed with nitrogen for 15 minutes. Pd(PPh3)4 (40 mg, 0.035 mmol) was added in one portion and the reaction mixture was stirred at reflux for 18 hours under nitrogen. The solvent was evaporated and the residue was purified by silica gel chromatography (200-300 mesh, eluting with a mixture of petroleum ether and ethyl acetate=1:1) to give (E)-methyl 4-(3-(7-(3,4-dimethoxyphenylamino)thiazolo[5,4-d]pyrimidin-5-yl)styryl)benzoate (90 mg, 37%) as a yellow sold. LC-MS: 525 [M+H]+, tR=1.89 min.
