A mixture of (5Z,8Z,11Z,14Z,17Z)-icosa-5,8,11,14,17-pentaen-1-ol, (1.00 g, 3.47 mmol), tetrabutylammonium chloride (0.24 g, 0.87 mmol) and t-butyl □-bromo propionate (3.62 g, 17.3 mmol) was dissolved in toluene (36 mL) and placed under nitrogen. An aqueous solution of sodium hydroxide (50%, 8 mL) was added slowly under vigorous stirring and the resulting mixture was stirred at ambient temperature for twenty hours. Water was added and the mixture was extracted three times with ether. The combined organic extract was washed with brine, dried (Na2SO4), filtered and concentrated. The residue was purified by flash chromatography on silica gel using 2% ethyl acetate in heptane as eluent. Concentration of the appropriate fractions afforded 1.40 g (90% yield) of the title compound as an oil. 1H-NMR (300 MHz, CDCl3): δ 0.95 (t, 3H), 1.41 (d, 3H), 1.48 (s, 9H), 1.48-1.66 (m, 4H), 2.05 (m, 4H), 2.83 (m, 8H), 3.35 (m, 1H), 3.55 (m, 1H), 3.79 (q, 1H), 5.32-5.44 (m, 10H).
