Br[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH3:13].[Mg].Br[C:16]1[O:20][CH:19]=[C:18]([CH:21]=[O:22])[CH:17]=1.C([Li])(C)(C)C.Cl[Si:29]([CH3:32])([CH3:31])[CH3:30]>O1CCCC1.CCCCC>[OH:22][CH:21]([C:18]1[CH:17]=[C:16]([Si:29]([CH3:32])([CH3:31])[CH3:30])[O:20][CH:19]=1)[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH3:13]
A mixture of 1-bromododecane (3.45 g, 14 mmol) and magnesium turnings (349 mg, 14.5 mmol) in tetrahydrofuran (10 ml) was refluxed under argon for 1 hour. After cooling to 0 degrees, a solution of 5-bromo-3-furaldehyde (2.42 g, 14 mmol) in tetrahydrofuran (3 ml) was added and conditions maintained or 20 minutes The mixture was further cooled to -78 degrees and tert-butyl lithium (a 1.7 M solution in pentane; 9.77 ml, 1.67 mmol) was added dropwise, followed by chlorotrimethylsilane (5.27 ml, 41.5 mmol) after 20 minutes Stirring was continued overnight (12 hours) while the cooling bath attained room temperature. The mixture was quenched with saturated aqueous ammonium chloride, diluted with water (15 ml) and extracted with ethyl ether. Evaporation of the dried (magnesium sulfate) extract gave a brown oil, which was flash chromatographed on silica using 15% ethyl ether/petroleum ether. Fractions with Rf of about 0.25 on evaporation afforded the title trimethylsilylfuran as a pale yellow oil.
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