Br[C:2]1[CH:3]=[C:4]([O:10][CH3:11])[C:5]([O:8][CH3:9])=[N:6][CH:7]=1.[C:12]([Si:14]([CH3:17])([CH3:16])[CH3:15])#[CH:13]>[Cu]I.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.C(N(CC)CC)C>[CH3:9][O:8][C:5]1[C:4]([O:10][CH3:11])=[CH:3][C:2]([C:13]#[C:12][Si:14]([CH3:17])([CH3:16])[CH3:15])=[CH:7][N:6]=1Copper (I) iodide (0.56 g, 2.9 mmol), bis(triphenylphosphine)palladium(II) dichloride (2.1 g, 2.9 mmol), and 5-bromo-2,3-dimethoxypyridine (12.8 g, 59 mmol) were added to triethylamine (80 ml) which produced a yellow suspension. The reaction was thoroughly degassed and ethynyltrimethylsilane (5.8 g, 59 mmol) was added to the stirred suspension which was then stirred for 16 hours and concentrated. The crude material was purified by column chromatography (SiO2; 0-10% ethyl acetate in petrol) to afford 2,3-dimethoxy-5-[(trimethylsilyl)ethynyl]pyridine (9.8 g, 71%).
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