Br[C:2]1[CH:3]=[C:4]([N+:9]([O-:11])=[O:10])[C:5]([CH3:8])=[N:6][CH:7]=1.[CH3:12][Si:13]([C:16]#[CH:17])([CH3:15])[CH3:14]>C(N(CC)CC)C.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.[Cu]I>[CH3:8][C:5]1[C:4]([N+:9]([O-:11])=[O:10])=[CH:3][C:2]([C:17]#[C:16][Si:13]([CH3:15])([CH3:14])[CH3:12])=[CH:7][N:6]=1
To a solution of 5-bromo-2-methyl-3-nitropyridine (9.38 g, 43.2 mmol) and (trimethylsilyl)acetylene (9.16 mL, 64.8 mmol) in triethylamine (300 mL) were added bis(triphenylphosphine)palladium(II) chloride (3.34 g, 4.75 mmol) and copper(I) iodide (1.64 g, 8.64 mmol). The reaction mixture was allowed to stir for 4 h at 80° C. and then cooled to rt and filtered through Celite®. The filter pad was washed with EtOAc and the filtrate was washed with saturated aqueous NaHCO3 (500 mL) then brine (500 mL). The organic solution was dried over Mg2SO4, filtered and concentrated. The residue was purified by column chromatography to give 2-methyl-3-nitro-5-[(trimethylsilyl)ethynyl]pyridine (9.22 g, 91%). LCMS (FAL): Rt=11.04 min, m/z=235.1 (M+H).
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