A slurry of 161 mg (0.50 mmol) 3-bromo-5-[1-(2-pyrrolidin-1-yl-ethyl)-1H-pyrazol-4-yl]-pyridine, 167 mg (0.55 mmol) 2-(5-Chloro-2-fluoro-phenyl)-[1,8]naphthyridine-4-boronic acid and 50.4 mg (0.6 mmol) sodium bicarbonate in 2 ml DMF and 0.5 ml water was heated at 80° C. under nitrogen. Then 7.0 mg (0.01 mmol) bis-(triphenylphosphine)-palladium(II)-chloride were added. The reaction mixture was stirred for 40 hours at 80° C. Water was added, the resulting precipitate was filtered off and washed with water. The residue was chromatographed on a silica gel column with dichloromethane/methanol as eluent yielding 2-(5-Chloro-2-fluoro-phenyl)-4-{5-[1-(2-pyrrolidin-1-yl-ethyl)-1H-pyrazol-4-yl]-pyridin-3-yl}-[1,8]naphthyridine as colourless crystals; HPLC-MS: 1.67 min, [M+H] 499.
