Ethyl Bromide → (Z,Z)-5,8-tetradecadien-2-yn-1-ol

Participants

Reaction Conditions

Reaction Steps

A solution off ethylmagnesium bromide in THF (10 ml) was prepared from magnesium (1.4 g, 57.7 mmol) and ethyl bromide (7.7 g, 71 mmol). Propargyl alcohol (1.53 g, 27.4 mmol) in dry THF (6 ml) was then added dropwise to the above ethylmagnesium bromide solution at 5° C. with vigorous stirring. The resulting viscous mixture was stirred at 23° C. under argon for twenty minutes. Cuprous chloride (0.14 g) was added and the reaction mixture was further stirred for twenty minutes. A solution of (Z,Z)-1-chloro-2,5-undecadiene (3.4 g, 18.2 mmol) in THF (2.0 ml) was then added dropwise to the above mentioned mixture over a period of twenty five minutes, at 20° C. The reaction mixture was stirred at 50° C. under argon for 18 h. The THF was removed at ~35° C. on a rotary evaporator and the resulting residue was treated with cold 1.5N H2SO4 (150 ml). It was extracted with ether, washed with water, and dried over Na2SO4. Evaporation of ether at reduced pressure gave 3.7 g of light yellow oil which was chromatographed on 70 g of silica gel. Elution with ether-petroleum ether (1:3) gave 2.3 g (61%) of (Z,Z)-5,8-tetradecadien-2-yl-1-ol which was evaporatively distilled at 137°-140° C./0.3 mm Hg as a colorless liquid.

Provenance & Evidence