The productivity of ethyl 3-hydroxybutyratecould be 96.60% under the following optimum conditions: 3-hydroxybutyric acid 0.1mol, ethanol 0.12mol, paratoluenesulfonic acid 0.7175 g, cyclohexane 50 mL,CaO18.70 g and reaction time 3h.

• 当0.；1mol 3-羟基丁酸；