[OH-:1].[K+].[CH3:3][O:4][C:5]1[CH:10]=[C:9]([O:11][CH3:12])[CH:8]=[CH:7][C:6]=1[CH:13]([CH2:17][CH2:18][CH2:19][CH2:20][CH3:21])CC#N.Cl.CCCCC.[CH2:28]([OH:31])[CH2:29]O>>[CH3:3][O:4][C:5]1[CH:10]=[C:9]([O:11][CH3:12])[CH:8]=[CH:7][C:6]=1[CH:13]([CH2:17][CH2:18][CH2:19][CH2:20][CH3:21])[CH2:29][C:28]([OH:31])=[O:1]1.00 g (17.8 mmol) of potassium hydroxide was added to a solution of 1.27 g (4.86 mmol) of (-)-2-(2,4-dimethoxyphenyl)heptyl cyanide [prepared as described in step (ii) above] in 6 ml of ethylene glycol, and the resulting mixture was heated under reflux for 2.5 hours in an atmosphere of nitrogen. At the end of this time, the reaction mixture was cooled to room temperature, after which it was acidified with 1 N aqueous hydrochloric acid and then extracted with diethyl ether. The extract was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate, after which the solvent was removed by distillation under reduced pressure. The resulting residue was purified by column chromatography through 100 g of silica gel, using a 1:2 by volume mixture of ethyl acetate and hexane as the eluent, to give 1.19 g (yield 87%) of the title compound as crystals, melting at 51-52° C. (from pentane).
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