[CH3:1]/[C:2](=[CH:9]\[C:10]1[CH:15]=[CH:14][C:13]([CH3:16])=[CH:12][CH:11]=1)/[CH2:3][CH2:4][C:5](OC)=[O:6].[H-].[Al+3].[Li+].[H-].[H-].[H-]>C1COCC1>[CH3:1]/[C:2](=[CH:9]\[C:10]1[CH:15]=[CH:14][C:13]([CH3:16])=[CH:12][CH:11]=1)/[CH2:3][CH2:4][CH2:5][OH:6]A solution of methyl (4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate (17.18 g, 0.079 mol) in dry THF (300 ml) was treated, at −78° C. under nitrogen, with solid lithium aluminum hydride (3.15 g, 0.079 mol) in one portion. After 5 minutes the cooling bath was removed and the reaction allowed to reach room temperature and then cooled to 0° C. and treated successively with water (3.15 ml), 5% aqueous sodium hydroxide (9.45 ml) and water (3.15 ml). The reaction was stirred at room temperature for 30 minutes. Anhydrous solid sodium sulfate was added (10 g) and stirring continued for 5 minutes. The solid was filtered off, rinsed with diethyl ether and solvents were removed under vacuum. The product was purified by column chromatography on silica gel (eluent: heptanes/ethyl acetate 5:1 to 1:1) followed by bulb-to-bulb distillation (120° C./0.001 mbar). 12.54 g (yield=66%) of the desired product were obtained.
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