P(=O)([O-])O[C:3](CC)(CC)[S:4][C:5]1[CH:10]=[CH:9][C:8]([CH3:11])=[CH:7][CH:6]=1.[Li]CCCC.[Si:23]([O:30][C@H:31]([CH3:34])[CH:32]=O)([C:26]([CH3:29])([CH3:28])[CH3:27])([CH3:25])[CH3:24]>O1CCCC1>[Si:23]([O:30][C@H:31]([CH3:34])/[CH:32]=[CH:3]/[S:4][C:5]1[CH:10]=[CH:9][C:8]([CH3:11])=[CH:7][CH:6]=1)([C:26]([CH3:29])([CH3:28])[CH3:27])([CH3:25])[CH3:24]Under the nitrogen atmosphere, 3.02 g (11 mmole) of diethyl-p-methylphenylthiomethyl phosphonate was dissolved in 50 ml of anhydrous tetrahydrofuran and after lowering the reaction temperature to -78° C., 6.25 ml (10 mmole) of 1.6M n-BuLi was added to the reaction mixture for ten minutes, and the resultant mixture was agitated at the temperature of -78° C. for 30 minutes. At the same temperature, 1.87 g (10 mmole) of (2R)-2-(t-butyldimethylsilyloxy)propanal diluted with 10 ml of anhydrous tetrahydrofuran was added to the said mixture and the reaction temperature was slowly raised from -78° C. to 0° C., and then the the mixture agitated at 0° C. for another one hour. Once the reaction was completed, the reaction was quenched by adding saturated ammonium chloride solution. After the work-up treatment in the same manner as did in method A of EXAMPLE 32, 2.8 g of crude product was obtained. The crude product was purified by a column chromatography (using n-hexane containing 1% diethyl ether as an eluent), thereby obtaining 2.5 g of desired compound having E/Z ratio of over 100/1 (yield: 81%) stereoselectively.
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