Using menthol and L-lactic acid as raw materials, L-Menthyl lactate was obtained by dehydration with cyclohexane, esterification, and purification. The effects of reaction time, alcohol-acid molar ratio, and catalyst amount on the reaction were studied. The optimal process conditions were determined as follows: n(menthol):n(L-lactic acid) = 1.2:1.0, catalyst 2% of the total weight of raw materials, cyclohexane heating under reflux to dehydrate, reaction for 6 h, and vacuum distillation to 120℃/400 Pa. The residue was recrystallized to obtain a white needle-like crystalline product with a yield of over 80% and a purity of 99%.
Author's Affiliation: Hunan Pharmaceutical Industry Research Institute
2008, Issue 3, <>
