[CH3:1][O:2][C:3]1[CH:18]=[CH:17][C:6]([CH2:7][C:8]2[CH:16]=[CH:15][C:11]([C:12]([OH:14])=[O:13])=[CH:10][CH:9]=2)=[CH:5][CH:4]=1.[Na].Cl.C1(C(O)=O)CCCCC=1>C(O)CC(C)C>[CH3:1][O:2][C:3]1[CH:4]=[CH:5][C:6]([CH2:7][CH:8]2[CH2:9][CH2:10][CH:11]([C:12]([OH:14])=[O:13])[CH2:15][CH2:16]2)=[CH:17][CH:18]=1A solution of 49.5 g. of 4-(4-methoxybenzyl)benzoic acid (Example 1c) in 1000 ml. of isoamyl alcohol was heated at reflux and 109 g. of sodium was added in pieces over a 40 minute period. The reaction mixture was heated under reflux for three hours, then cooled and steam distilled until 2.5 liters of distillate was obtained. The resulting aqueous solution was acidified with concentrated hydrochloric acid and extracted with ether. The ether extracts were dried over anhydrous magnesium sulfate and the solvent removed to give 34 g. of a crystalline residue comprising a mixture of the desired compound with the corresponding cyclohex-1-enecarboxylic acid. The latter mixture was dissolved in 170 ml. of ethanol and hydrogenated in the presence of 3 g. of 10% palladium-on-carbon catalyst. The catalyst was filtered off and the solvent removed to give 34 g. of 4-(4-methoxybenzyl)cyclohexanecarboxylic acid, used directly in the next reaction without further purification.
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