[CH2:1]([O:3][C:4]1[CH:14]=[C:13](I)[CH:12]=[CH:11][C:5]=1[C:6]([O:8][CH2:9][CH3:10])=[O:7])[CH3:2].[CH3:16][Si:17]([C:20]#[CH:21])([CH3:19])[CH3:18].O>C(N(CC)CC)C.CN(C)C=O.[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>[CH2:1]([O:3][C:4]1[CH:14]=[C:13]([C:21]#[C:20][Si:17]([CH3:19])([CH3:18])[CH3:16])[CH:12]=[CH:11][C:5]=1[C:6]([O:8][CH2:9][CH3:10])=[O:7])[CH3:2]
Ethyl 2-ethoxy-4-iodobenzoate (0.763 g, 2.38 mmol, example 14), copper(I) iodide (0.0227 g, 0.119 mmol), dichlorobis(triphenylphosphine)palladium(II) (0.167 g, 0.238 mmol) and (trimethylsilyl)acetylene (0.404 mL, 2.86 mmol) were dissolved under nitrogen in a flame-dried flask in a mixture of triethylamine (3.5 mL) and dimethylformamide (3.5 mL). The reaction mixture was heated at 50° C. for 2 h and then allowed to cool. Water (100 mL) was added and the mixture was extracted with diethyl ether (3×100 mL). The combined organic phases were washed with water (100 mL), brine (100 mL), dried over Sodium sulfate and evaporated. Purification of the crude residue by flash column chromatography (silica gel, eluting with 10% ethyl acetate in hexanes) gave ethyl 2-ethoxy-4-trimethylsilanylethynyl-benzoate as a yellow oil (0.624 g, 90%).
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