General procedure for the synthesis of cis-4-hydroxycyclohexanecarboxylic acid from methyl cis-4-hydroxycyclohexanecarboxylate: 20 g of methyl cis-4-hydroxycyclohexanecarboxylate was dissolved in 80 mL of methanol and cooled in an ice-water bath. Slowly 40mL of 5 mol/L sodium hydroxide solution was added dropwise, and after completion of the dropwise addition, the reaction mixture was stirred at room temperature overnight. After the reaction was completed, 150 mL of water was added to dilute it. The mixture was extracted twice with ethyl acetate and the organic phase was discarded. The aqueous phase was adjusted to pH 3 with 1 mol/L HCl and extracted twice with 50 mL of ethyl acetate to combine the organic phases. The organic phase was washed twice with saturated saline in turn, dried and decolorized. After filtration, ethyl acetate was recovered by distillation under reduced pressure to give 16 g of white solid product cis-4-hydroxycyclohexanecarboxylic acid in 90% yield.
