Br[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][N:3]=1.[Br:8][C:9]1[CH:10]=[C:11](B(O)O)[CH:12]=[CH:13][CH:14]=1.C(COC)OC.C(=O)([O-])[O-].[K+].[K+]>O.C(OCC)(=O)C.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[Br:8][C:9]1[CH:14]=[C:13]([C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][N:3]=2)[CH:12]=[CH:11][CH:10]=1A mixture of 2-bromopyridine (4.8 g, 30.33 mmol), 3-bromophenyl boronic acid (4.06 g, 20.22 mmol), glyme (35 mL), tetrakis(triphenylphosphine)palladium(0) (0.4 g) and a solution of potassium carbonate (7.6 g, 55 mmol) in water (35 mL) was stirred well at reflux under nitrogen overnight. After cooling, the reaction mixture was diluted with ethyl acetate (600 mL) and washed with water (3×200 mL). The solvent and excess 2-bromopyridine were removed on a rotary evaporator (bath temperature=75° C.) and the crude product was purified by chromatography on silica (110 g) with 2% ethyl acetate in heptane (6 L) to produce 1 (3.55 g, 75%).
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