1: n-decyl-triphenylphosphonium bromide With sodium hexamethyldisilazane in tetrahydrofuran T=-40 - -20°C; 2: 4-pentynal in tetrahydrofuran T=-40 - 0°C; Wittig olefination;

1: 1.) n-BuLi / 1.) n-hexane, THF, 1 h, -10 deg C, 2.) n-hexane, THF, HMPT, 11 h, room temperature 2: p-toluenesulfonic acid monohydrate / methanol / 18 h / Ambient temperature 3: 83 percent / H2, quinoline / 5percent Pd/BaSO4 / methanol / 760 Torr / Ambient temperature 4: pyridine / 9 h / 0 °C 5: dimethylsulfoxide / 18 h / Ambient temperature 6: 1.) (i-Bu)2AlH, 2.) tartaric acid / 1.) n-hexane, ether, 1 h, -20 deg C; 1 h, RT, 2.) n-hexane, ether, water, 1 h 7: 1.) triphenylphosphine / 1.) CH2Cl2, 0 deg C, 2.) CH2Cl2, 15 min, 0 deg C 8: 70 percent / n-BuLi / hexane; tetrahydrofuran / 1.) 30 min, -70 deg C, 2.) 1 h, room temperature View Scheme