text: A solution of methyl(cyano)cuprate (Solution A) was prepared as follows: to a suspension of 0.35 g (3.91 mmol) of copper(I) cyanide in 5 mL of tetrahydrofuran under argon at 0° was added dropwise over about 5 minutes 2.76 mL of a solution of methyllithium in ethyl ether (1.4 M, 3.86 mmol). The colorless solution was stirred for 10 minutes at 0°, warmed to 25° over 30 minutes, then cooled again to 0°. Separately, a solution of the lithium salt of (±)-cis-4-benzyloxy-2,3-epoxy-1-butanol (Solution B) was prepared as follows: to a solution of 0.5 g (2.58 mmol) of the epoxy alcohol and 0.90 g (21.4 mmol) of lithium chloride in 10 mL of tetrahydrofuran under argon at −78° was added dropwise 1.65 mL of a solution of n-butyllithium in hexane (1.56 M, 2.58 mmol). The solution was stirred for 5 minutes at −78°, allowed to warm to 0°, and then stirred at that temperature for 10 minutes. The reaction was effected by the addition of Solution A to Solution B via cannula at 0° followed by warming to room temperature over 2 hours. The reaction mixture was then stirred for a further 12 hours and then cautiously treated with 5 mL of saturated aqueous ammonium chloride. The mixture was stirred for 1–2 hours to aid removal of copper residues. Ethyl ether (20 mL) was then added, and the organic layer was separated. The aqueous phase was extracted twice with 20 mL of ethyl ether, and the combined organic phases were dried over magnesium sulfate, filtered, and concentrated to give 0.51 g of the product as a colorless oil (95%), IR (film) 3400, 3100, 3060, 3030, 2970, 2930, 2870, 1600, 1500, 1465, 1445, 1385, 1370, 1320, 1285, 1210, 1180, 1120, 1100, 1075, 1030, 1020, 980, 905, 830, 750, 730, 710, 695 cm–1; 1H NMR (CDCl) δ 0.90 (t, J = 6.0 Hz, 3 H), 1.37–1.53 (m, 2 H), 3.20 (br s, 2 H), 3.40–3.65 (m, 4 H), 4.48 (s, 2 H), 7.29 (s, 5 H).