Essential oils are widely used in cosmetic and personal care products. These essential oils such as menthol, limonene, rose oil, and jasmine oil are extracted from plants and also prepared in the laboratory. Menthol is the most common cyclic monoterpene alcohol, which has been produced due to its demand in various industries worldwide. In the literature, there were many protocols reported for the synthesis of menthols from natural or synthetic precursors. In this review, we summarized the synthesis of menthol from citral, citronellal, and pulegone using various heterogeneous catalysts under different conditions. Considering the world’s demand for menthol in food preservatives and scents, the right optimization of citronella extraction and its conversion is highly important. It can be used in pharmaceutical industries due to the presence of active substances. The presence of flavored compounds has the potential to enhance the nutritional value of food. This review will be very helpful for researchers who are working on menthol synthesis in industry and institutions. The determination of direct conversion to menthol over indirect conversion can be proven to be effective for industrial use as it will be more economical and time-saving.

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概述：利用多相催化合成薄荷醇

精油广泛用于化妆品和个人护理产品。这些精油如薄荷醇、柠檬烯、玫瑰油和茉莉油是从植物中提取的，也是在实验室中制备的。薄荷醇是最常见的环状单萜醇，由于全球各个行业的需求而产生。在文献中，报道了许多从天然或合成前体合成薄荷醇的方案。在这篇综述中，我们总结了在不同条件下使用各种非均相催化剂从柠檬醛、香茅醛和胡薄荷酮合成薄荷醇的过程。考虑到世界对食品防腐剂和香料中薄荷醇的需求，正确优化香茅提取及其转化非常重要。由于活性物质的存在，它可以用于制药工业。调味化合物的存在有可能提高食品的营养价值。本综述对于工业界和机构中从事薄荷醇合成研究的研究人员将非常有帮助。直接转化为薄荷醇相对于间接转化的测定已被证明对于工业用途是有效的，因为它将更加经济和节省时间。