[C:1]([Si:5]([C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)([C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)Cl)([CH3:4])([CH3:3])[CH3:2].[CH2:19]([OH:25])[CH2:20][CH2:21][CH2:22][C:23]#[CH:24].N1C=CN=C1>C(Cl)Cl>[Si:5]([O:25][CH2:19][CH2:20][CH2:21][CH2:22][C:23]#[CH:24])([C:1]([CH3:4])([CH3:3])[CH3:2])([C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1tert-Butyldiphenylchlorosilane (3.2 mL, 12.4 mmol) was added dropwise to a stirring, 0° C. solution of 5-hexyn-1-ol (4, 1.07 g, 10.9 mmol) and anhydrous imidazole (1.84 g, 27.1 mmol) in anhydrous CH2Cl2 (20 mL) under an argon atmosphere. After complete addition, the reaction mixture was stirred at room temperature for 12 hours, then quenched with saturated aq. NH4Cl solution (50 mL) and extracted with Et2O (3×50 mL). The combined ethereal extracts were washed with saturated aq. NaCl solution (25 mL), dried over NaSO4, and the solvent was removed in vacuo. The residue was purified by flash chromatography (5% ethyl acetate/hexane) to yield 1-tert-butyldiphenylsilyloxy-hex-5-yne (5) (3.54 g, 10.5 mmol, 96%) as a colorless oil. TLC: 5% EtOAc/hexanes, Rf≈0.65; 1H NMR (400 MHz, CDCl3) δ 7.77-7.65 (m, 4H), 7.40-7.30 (m, 6H), 3.70 (t, 2H, J=5.6 Hz), 2.40-2.25 (m, 2H), 2.05 (t, 1H, J=2.8 Hz), 1.90-1.70 (m, 4H), 1.18 (s, 9H).
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