A slurry of 352 mg (2.04 mmol) 2-amino-5-bromo-pyridine, 678 mg (2.24 mmol) 2-(5-chloro-2-fluoro-phenyl)-[1,8]naphthyridine-4-boronic acid and 1.33 g (4.07 mmol) cesium carbonate in 10 ml dioxane and 2 ml water was heated to 80° C. under nitrogen. Then 118 mg (0.10 mmol) tetrakis-(triphenylphosphine)-palladium(0) were added and the reaction mixture was stirred for 1 hour at 100° C. The reaction mixture was cooled to room temperature and water and dichloromethane were added. The resulting precipitate was filtered off, washed with water and dried in vacuo yielding 5-[2-(5-chloro-2-fluoro-phenyl)-[1,8]naphthyridin-4-yl]-pyridin-2-ylamine as brown crystals; HPLC-MS: 1.43 min, [M+H] 351.
