[CH3:1][Si:2]([CH3:8])([CH3:7])[CH2:3][CH2:4][CH2:5]Br.[Mg].Br[CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][O:22]C1CCCCO1.[Cl-].[Li+].[Cl-]>O1CCCC1>[CH3:1][Si:2]([CH3:8])([CH3:7])[CH2:3][CH2:4][CH2:5][CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][OH:22]
The Grignard reagent prepared from 31.6 g. 3-(trimethylsilyl)propyl bromide and 4.0 g. magnesium turnings in 100 ml. dry tetrahydrofuran was dropwise added under argon to a cold (-20°) stirred solution of 33 g. 11-bromoundecyltetrahydropyranyl ether, 82 mg. lithium chloride and 125 mg. cuprus chloride in 250 mg. dry tetrahydrofuran. After the reagents had been combined, the solution was left to stir at room temperature for 17 hr. The reaction was diluted with 400 ml. 10% hydrochloric acid solution, the layers were separated, and the aqueous layer was extracted three times with 150 ml. portions of ether. The combined organic solutions were washed with brine, dried with anhydrous magnesium sulfate, and evaporated to 36.7 g. milky liquid. This intermediate tetrahydropyranyl ether was dissolved into 250 ml. ethanol and 15 ml. concentrated hydrochloric acid and stirred at reflux for 40 hr. The solvents were evaporated, the residue was re-dissolved into 300 ml. methylene chloride, and this solution was passed through a pad of hydrous magnesium silicate. The methylene chloride was evaporated and the residue was distilled in vacuo to yield a colorless liquid.
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