Br[C:2]1[CH:3]=[C:4]([C:10]([Br:13])=[CH:11][N:12]=1)[C:5]([O:7][CH2:8][CH3:9])=[O:6].[CH3:14][C:15]1[CH:16]=[C:17](B(O)O)[CH:18]=[N:19][CH:20]=1.C(=O)([O-])[O-].[Cs+].[Cs+].O>CN(C)C=O>[Br:13][C:10]1[C:4]([C:5]([O:7][CH2:8][CH3:9])=[O:6])=[CH:3][C:2]([C:17]2[CH:18]=[N:19][CH:20]=[C:15]([CH3:14])[CH:16]=2)=[N:12][CH:11]=1
To a solution ethyl 2,5-dibromoisonicotinate (1-2, 1.5 g, 4.86 mmol) in degassed dimethylformamide (24 mL) at 25° C. was added (5-methylpyridin-3-yl)boronic acid (0.665 g, 4.86 mmol), PdCl2dppf (0.355 g, 0.486 mmol), cesium carbonate (4.75 g, 14.6 mmol) and water (0.262 mL, 14.57 mmol). The reaction flask was purged with nitrogen, sealed and stirred at 50° C. overnight. The crude reaction mixture was partitioned between water and EtOAc, separating layers and washing the organic layer with saturated sodium bicarbonate solution and brine. The solvent was removed by rotary evaporation and the crude product was purified by normal phase column chromatography (0 to 50% EtOAc in hexanes) to afford the product (1-3) as a white solid. ESI+MS[M]+C14H13BrN2O2=321.0.
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