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 1h. After cooling to 0°, a solution of 5-bromo-3-furaldehyde (2.42 g, 14 mmol) in tetrahydrofuran (3 ml) was added and conditions maintained for 20 min. The mixture was further cooled to -78° and tert-butyl lithium (a 1.7M solution in pentane; 9.77 ml, 1.67 mmol) was added dropwise, followed by chlorotrimethylsilane (5.27 ml, 41.5 mmol) after 20 min. Stirring was continued overnight (12h) 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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