6-bromohex-1-ynyl(trimethyl)silane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 1-trimethylsilyl(hex-1-yn-6-ol) (32.6 g, 190 mmol) and pyridine (0.38 mL) dissolved in diethyl ether (100 mL) was added slowly phosphorus tribromide (7.1 mL, 75 mmol) in diethyl ether (20 mL). Upon addition a precipitate formed and the heterogeneous solution was stirred at room temperature overnight. The mixture was then heated at reflux for 2.5 hours and, upon cooling, was poured onto ice, washed with water, sodium bicarbonate solution, brine and dried (MgSO4). Evaporation of solvent under reduced pressure gave a residue which was distilled (b.p. 80° C., 3.5 mm Hg) to give 22 g (50%) of product. 1H NMR (CDCl3) δ: 0.14 (s, 9H), 1.64-1.72 (quintet, 2H), 1.91-2.02 (quintet, 2H), 2.27 (t, 2H), 3.44 (t, 2H) ppm. Upon addition a precipitate formed The mixture was then heated at reflux for 2.5 hours upon cooling was poured onto ice washed with water, sodium bicarbonate solution, brine dried (MgSO4) Evaporation of solvent under reduced pressure gave a residue which was distilled (b.p. 80° C., 3.5 mm Hg)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 1-trimethylsilyl(hex-1-yn-6-ol) (32.6 g, 190 mmol) and pyridine (0.38 mL) dissolved in diethyl ether (100 mL) was added slowly phosphorus tribromide (7.1 mL, 75 mmol) in diethyl ether (20 mL). Upon addition a precipitate formed and the heterogeneous solution was stirred at room temperature overnight. The mixture was then heated at reflux for 2.5 hours and, upon cooling, was poured onto ice, washed with water, sodium bicarbonate solution, brine and dried (MgSO4). Evaporation of solvent under reduced pressure gave a residue which was distilled (b.p. 80° C., 3.5 mm Hg) to give 22 g (50%) of product. 1H NMR (CDCl3) δ: 0.14 (s, 9H), 1.64-1.72 (quintet, 2H), 1.91-2.02 (quintet, 2H), 2.27 (t, 2H), 3.44 (t, 2H) ppm. Upon addition a precipitate formed The mixture was then heated at reflux for 2.5 hours upon cooling was poured onto ice washed with water, sodium bicarbonate solution, brine dried (MgSO4) Evaporation of solvent under reduced pressure gave a residue which was distilled (b.p. 80° C., 3.5 mm Hg)