Br[C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([CH3:8])[N:3]=1.C[Si]([C:13]#[CH:14])(C)C.[OH-].[Na+].Cl>C(N(CC)CC)C.CO.[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:13]([C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([CH3:8])[N:3]=1)#[CH:14]
A solution of 2-bromo-6-methylpyridine (0.5 g, 2.9 mmol) and (trimethylsilyl)acetylene (0.29 g, 2.9 mmol) in triethylamine (15 mL) is purged with argon. Copper(I) iodide (11 mg, 0.06 mmol) and (PPh3)2PdCl2 (42 mg, 0.06 mmol) are added and the reaction is stirred under argon at room temperature for 2 h. The solvent is removed in vacuo and the residue is diluted in ethyl acetate (50 mL) and water (50 mL). The organic is separated and washed with brine. The solvent is removed to afford a dark oil. This oil is diluted in methanol (50 mL) and treated with a 1 N sodium hydroxide solution (10 mL) and stirred for 3 h at room temperature. The aqueous is neutralized with 1 N hydrochloric acid and extracted with ethyl acetate. The solvent is removed in vacuo to afford a dark oil that is purified by SiO2 column chromatography to yield 1.16 g (24%) of the title compound as a light yellow oil.
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