[O:1]([CH:9]1[CH2:13][C:12](=[O:14])[CH:11]=[CH:10]1)[Si:2]([C:5]([CH3:8])([CH3:7])[CH3:6])([CH3:4])[CH3:3].[I-].[Li+].[H-].[Al+3].[Li+].[H-].[H-].[H-]>C(OCC)C>[Si:2]([O:1][C@@H:9]1[CH2:13][C@H:12]([OH:14])[CH:11]=[CH:10]1)([C:5]([CH3:8])([CH3:7])[CH3:6])([CH3:4])[CH3:3]A mechanically stirred solution of 4-tert-butyldimethylsiloxy-2-cyclopentenone (1.01 g, 4.76 mmol) in anhydrous ethyl ether (20 mL) under an atmosphere of argon is treated with lithium iodide (3.20 g, 23.9 mmol). The mixture is cooled to -78° C. and treated with lithium aluminum hydride (184 mg, 4.85 mmol) in one portion. The reaction is then stirred for 90 minutes. It is then quenched by slow addition of aqueous sodium hydroxide (1N, 23 mL) at a rate that maintains the temperature of the reaction below 20° C. The resulting suspension is then filtered through a pad of diatomaceous earth and the pad is subsequently rinsed with ether. The filtrate phases are separated and the aqueous phase is extracted with ether (20 mL). The organic phase and organic extract are combined, rinsed with aqueous sodium hydroxide (1N, 20 mL), brine (20 mL), dried over anhydrous magnesium sulfate, filtered and concentrated under vacuum (40° C., 20 mmHg). The residue is then purified by Kugelrohr distillation (60°-80° C., 1 mmHg) to provide the title compound. (820 mg, 80% yield) as a colorless oil; cis/trans/1-2+1-4 addition, 88.5/3.3/8.2.
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