[CH3:1][C:2]1([C:13]([O:15]CC(C)C)=[O:14])[CH2:7][CH2:6][CH:5]([O:8][CH2:9][CH2:10][O:11][CH3:12])[CH2:4][CH2:3]1.[OH-].[Na+]>O1CCOCC1>[CH3:1][C:2]1([C:13]([OH:15])=[O:14])[CH2:3][CH2:4][CH:5]([O:8][CH2:9][CH2:10][O:11][CH3:12])[CH2:6][CH2:7]1A mixture of isobutyl 1-methyl-4-(2-methoxyethoxy)cyclohexanecarboxylate (D68, 27 g, 49.6 mmol), 1,4-dioxane (100 mL) and 3M aqueous sodium hydroxide (100 mL, 300 mmol) was heated at 100° C. for 18 h then cooled and partitioned between water and diethyl ether. The aqueous phase was acidified and extracted with ethyl acetate to give the desired product. Unreacted starting material remained in the ether wash, so the ether was evaporated and the residue dissolved in a mixture of THF (100 mL), methanol (100 mL), and 6M aqueous sodium hydroxide (100 mL) and heated at 65° C. for 18 h then worked up as before to give additional product, which was combined to give 1-methyl-4-(2-methoxyethoxy)cyclohexanecarboxylic acid (9.5 g, 43.9 mmol, 89% yield) as a pale yellow oil.
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