[CH2:1]([OH:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[H-].[Na+].Br[CH2:12][C:13]#[C:14][C@@H:15]([O:21][C:22](=[O:24])[CH3:23])[CH2:16][CH2:17][CH2:18][CH2:19][CH3:20]>CN(C)C=O.O>[CH2:1]([O:8][CH2:12][C:13]#[C:14][C@@H:15]([O:21][C:22](=[O:24])[CH3:23])[CH2:16][CH2:17][CH2:18][CH2:19][CH3:20])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1Benzyl alcohol (1 molar equivalent) is added dropwise to a stirred suspension of sodium hydride (1 molar equivalent) in dry dimethylformamide maintained at 0° to 5° C. throughout the addition. The reaction mixture is allowed to warm to and then is maintained at room temperature for 1/2 hour. After cooling to 0° to 5° C., the reaction mixture is treated with 1-bromo-4(S)-acetyloxy-2-nonyne (1 molar equivalent) added dropwise over 1/2 hour. The resulting reaction mixture is stirred at ambient temperature for 2 hours and then diluted with water providing a turbid mixture which is extracted with ether. The organic extract is washed with water and saturated aqueous brine, dried over sodium sulfate and filtered. Evaporation (in vacuo at 40° to 50° C.) of the filtrate leaves an oily residue which is distilled to provide the pure title compound.
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