Cl.Br[C:3]1[CH:8]=[CH:7][N:6]=[CH:5][C:4]=1[CH3:9].C(N(CC)CC)C.[CH3:17][Si:18]([C:21]#[CH:22])([CH3:20])[CH3:19]>C1COCC1.[Cu](I)I>[CH3:9][C:4]1[CH:5]=[N:6][CH:7]=[CH:8][C:3]=1[C:22]#[C:21][Si:18]([CH3:20])([CH3:19])[CH3:17]To a solution of 4-bromo-3-methyl pyridine hydrochloride (5.0 g, 24.0 mmol) in THF (degassed, 80 mL) was added copper iodide (450 mg, 2.40 mmol) and triethylamine (20.0 mL, 143.9 mmol). After degassing for 15 min, palladium tetrakis triphenylphosphine (830 mg, 0.72 mmol) and trimethylsilylacetylene (6.10 mL, 43.16 mmol) were added. The mixture was heated at 50° C. for 16 h then cooled to rt and filtered. The crude residue was purified via silica gel chromatography (EtOAc-Hexanes, 10%) to afford the title compound (3.95 g, 87%) as clear but dark oil.
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