[Si:1]([O:8][C@H:9]([C:14]1[CH:19]=[CH:18][CH:17]=[C:16]([Cl:20])[CH:15]=1)[C:10](OC)=[O:11])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[H-].C([Al+]CC(C)C)C(C)C.O.C(OCC)(=O)C>CCCCCC.C1(C)C=CC=CC=1>[Si:1]([O:8][C@H:9]([C:14]1[CH:19]=[CH:18][CH:17]=[C:16]([Cl:20])[CH:15]=1)[CH:10]=[O:11])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]
A solution of 26 g of methyl (R)-α-t-butyldimethylsilyloxy-3-chlorophenylacetate (prepared as described in Preparation 48) in a mixture of 1000 ml of anhydrous hexane and 500 ml of dry toluene was cooled to -60° C., and then 124 ml of a 1M solution of diisobutylaluminum hydride in hexane were added dropwise to the cooled solution. The resulting mixture was stirred at the same temperature for 3 hours, after which 10 ml of water were added to it, and the temperature of the mixture was gradually allowed to rise to room temperature. The reaction mixture was then mixed with water and ethyl acetate, after which it was stirred for 30 minutes. Insoluble materials were filtered off using a Celite (trade mark) filter aid, and the ethyl acetate layer was separated from the filtrate and dried over anhydrous sodium sulfate. The ethyl acetate solvent was removed by distillation under reduced pressure, and the residue was purified by column chromatography through silica gel, using a 1:60 by volume mixture of ethyl acetate and hexane as the eluent, to give the title compound having an Rf=0.36 (thin layer chromatography over silica gel, using a 1:60 by volume mixture of ethyl acetate and hexane as the developing solvent).
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