[C:1]([O:4][C:5]1[C:6](Br)=[N:7][CH:8]=[CH:9][CH:10]=1)(=[O:3])[CH3:2].C(N(CC)CC)C.[C:19]([Si:21]([CH3:24])([CH3:23])[CH3:22])#[CH:20]>C1COCC1.[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:1]([O:4][C:5]1[C:6]([C:20]#[C:19][Si:21]([CH3:24])([CH3:23])[CH3:22])=[N:7][CH:8]=[CH:9][CH:10]=1)(=[O:3])[CH3:2]2-Bromopyridin-3-yl acetate (10 g, 46 mmol) was dissolved in THF (80 mL) and triethylamine (32 ml, 231 mmol), ethynyltrimethylsilane (19.5 ml, 139 mmol), and CuI (0.44 g, 23 mmol) were added. The mixture was degassed with argon for 15 minutes, then PdCl2(PPh3)2 (1.6 g, 2.3 mmol) was added and the mixture was stirred under argon at ambient temperature for 18 hours. The reaction was concentrated in vacuo, dissolved in 25% EtOAc in hexanes, filtered and purified over silica gel (25% ethyl acetate/hexanes) to afford 2-((trimethylsilyl)ethynyl)pyridin-3-yl acetate (9.7 g, 41 mmol).
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