In a reaction vessel equipped with a stirring device and a temperature control system, 100 wt. portions of 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate and 2 wt. portions of benzothiazole nitrate ionic liquid catalyst were added. Under sufficient stirring, the reaction temperature was controlled at 140 °C, and the transesterification reaction was carried out for 2 hours to produce 2,2,4-trimethyl-1,3-pentanediol isobutyrate and 2,2,4-trimethyl-1,3-pentanediol. Subsequently, the temperature was raised to 170-190 °C in the presence of an ionic liquid catalyst and distillation was carried out under reduced pressure at -0.003 MPa, resulting in 2,2,4-trimethyl-1,3-pentanediol diisobutyrate in 88.1% yield.
