[Br:1][C:2]1[CH:3]=[N:4][CH:5]=[C:6](I)[CH:7]=1.[O:9]1[CH2:13][C:12](=O)[N:11]=[C-:10]1.C1(P(C2C=CC=CC=2)C2C3[O:34]C4C(=CC=CC=4P(C4C=CC=CC=4)C4C=CC=CC=4)C(C)(C)C=3C=CC=2)C=CC=CC=1.C(=O)([O-])[O-].[Cs+].[Cs+]>C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.[Pd].[Pd].C1(C)C=CC=CC=1>[Br:1][C:2]1[CH:7]=[C:6]([N:11]2[CH2:12][CH2:13][O:9][C:10]2=[O:34])[CH:5]=[N:4][CH:3]=1An argon purged flask (100 mL) is charged with reagent 3-bromo-5-iodopyridine (200 mg, 0.704 mmol), 2-oxazolidone (61.3 mg, 0.704 mmol), tris(dibenzylideneacetone)dipalladium(0) (64.5 mg, 0.07 mmol), 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (61.1 mg, 0.106 mmol), and cesium carbonate (459 mg, 1.409 mmol). Toluene (bubbled with argon before use, 14 mL) is then added. The resulting mixture is heated at 90° C. under argon for 16 h. The mixture is filtered through diatomaceous earth and washed with MeOH (30 mL). The filtrate is concentrated. The resulting crude product is purified by normal phase chromatography using 0-4.5% MeOH in DCM as the gradient to afford 3-(5-bromo-pyridin-3-yl)-oxazolidin-2-one (60 mg, 35% yield).
불러오는 중…