1,6-Dibromohexane → 6-Bromohexylbut-3-ynyl ether

Participants

Reaction Conditions

Reaction Steps

A mixture of 50% w/v aqueous sodium hydroxide (2500 ml), 1,6-dibromohexane (2610 g) and tetra-butylammonium bromide (25 g) was warmed to 50° C., with stirring. But-3-yn-1-ol (500 g) was then added to the reaction mixture at such a rate as to ensure the content's temperature did not exceed 65° C. The reaction was left at 50° C. overnight before being cooled to room temperature. Tert-butyl methyl ether (2500 ml) and brine (2000 ml) was added to the cooled mixture and the layers allowed to separate. The ethereal layer was washed with water (2×2000 ml), brine (1×2000 ml), and then dried over anhydrous MgSO4. The solution was filtered and concentrated under reduced pressure to give crude product as a liquid. This was further purified by fractional distillation using a 60 cm vacuum jacketed Vigreux column at ca. 0.5 mbar. The product was obtained in the fraction which boiled at 92-98° C., to give the title compound (518 g), LC RT=6.16, δ (CDCl3) 3.55 (2H, t, J 6.9 Hz), 3.46 (2H, t, J 6.9 Hz), 3.41 (2H, t, J 6.9 Hz), 2.46 (2H, dt, J 2.5, 6.9 Hz), 1.98 (1H, t, J 2.5 Hz), 1.86 (2H, m), 1.59 (2H, m), 1.46 (2H, m), 1.38 (2H, m).

Provenance & Evidence