C([Li])(C)(C)C.Br[C:7]1[CH:12]=[CH:11][CH:10]=[C:9]([CH2:13][CH3:14])[N:8]=1.[CH2:15]([Sn:19](Cl)([CH2:24][CH2:25][CH2:26][CH3:27])[CH2:20][CH2:21][CH2:22][CH3:23])[CH2:16][CH2:17][CH3:18].O>CCCCC.C(OCC)C>[CH2:13]([C:9]1[CH:10]=[CH:11][CH:12]=[C:7]([Sn:19]([CH2:20][CH2:21][CH2:22][CH3:23])([CH2:24][CH2:25][CH2:26][CH3:27])[CH2:15][CH2:16][CH2:17][CH3:18])[N:8]=1)[CH3:14]Add under nitrogen a solution of tert-butyllithium in pentane (1.5; M, 80.3; mL, 120.5; mmol) dropwise over 1; hour to a cooled solution of 2-bromo-6-ethyl-pyridine (10.19; g, 54.77; mmol) in anhydrous diethyl ether (101.9; mL) at −78° C. at a rate so that the internal reaction temperature does not exceed −75° C. Stir 15; min and add tri-n-butyltin chloride (16.25; mL, 57.51; mmol) dropwise at a rate so that the internal reaction temperature does not exceed −70° C. Warm to room temperature, add water and separate the layers. Extract the aqueous phase once with diethyl ether. Dry the combined organic layers over sodium sulfate, filter and concentrate to give the title compound as a pale yellow liquid (24.05; g, 94%) that is subsequently used without further purification. 1H NMR (CDCl3) δ 0.88; (t, 9H), 1.09; (m, 6H), 1.32; (m, 9H), 1.56; (m, 6H), 1.57; (m, 6H), 2.80; (q, 2H), 6.95; (m, 1H), 7.17; (d, 1H), 7.38; (t, 1H).
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