A vial containing 6-bromo-3,4-dihydro-2H-[1,8]naphthyridine-1-carboxylic acid amide (350 mg, 1.4 mmol), bis(pinacolato)diboron (573 mg, 2.3 mmol), 1,1′-bis(diphenylphosphino)ferrocenedichloropalladium (II) (50 mg, 0.068 mmol) and potassium acetate (604 mg, 6.2 mmol) in 1,4-dioxane (10 mL) is flushed with Ar, sealed tightly and heated to 80° C. for 2 h. The reaction mixture is cooled to room temperature and a solution of 3-(5-bromo-pyridin-3-yl)-oxetan-3-ol (314 mg, 1.37 mmol) in 1,4-dioxane (4 mL), aqueous sodium carbonate solution (2M, 1.4 mL, 2.7 mmol) and additional 1,1′-bis(diphenylphosphino)ferrocenedichloropalladium (II) (50 mg, 0.068 mmol) are added. The mixture is flushed with Ar, sealed tightly and heated to 100° C. for 90 min. After cooling to room temperature the mixture is partitioned between water and EtOAc. The layers are separated and the aqueous is further extracted with EtOAc. The combined organic layers are washed with brine, dried (Na2SO4) and concentrated. To the residue is added MeOH to form a precipitate which is collected by filtration to afford the title compound (28 mg).
