Synthesis of para-menthane-3,8-diol from citronellal through Prins mechanism

Abstract

Para-menthan-3,8-diol (PMD) is a proven, highly effective mosquito repellent, but not yet popular in Vietnam. Synthesis of PMD contributes to the developement and the diversity of the products contain PMD in Vietnam. Moreover, these products also help to prevent the spread of the infectious diseases by mosquitoes. The study synthesized and purified para-menthan-3,8-diol from citronellal through Prins mechanism in Vietnamese conditions (H ~ 61%) with recommended optimal parameters including reaction temperature at 50⁰C, 0.25% sulfuric acid, the ratio of acid solution and citronellal (40: 1) and reaction time about 6 hours. Both of cis and trans PMD isomers were separated by column chromatoghraphy and identified structures by infra – red (IR) and NMR spectrometry.