An object of the present invention is to provide a method for manufacturing an optically active menthol having fewer steps, which generates less environmentally polluting waste because a catalytic reaction is involved in all of the steps, and is capable of saving a production cost. The present invention relates to a method for manufacturing an optically active menthol, including the following steps: A-1) asymmetrically hydrogenating at least one of geranial and neral to thereby obtain an optically active citronellal, B-1) conducting a ring-closure reaction of the optically active citronellal in the presence of an acid catalyst to thereby obtain an optically active isopulegol, and C-1) hydrogenating the optically active isopulegol to thereby obtain an optically active menthol.
本发明的目的是提供一种制造光学活性薄荷醇的方法,该方法步骤较少,由于所有步骤都涉及催化反应,因此产生的环境污染废物较少,并且能够节约生产成本。本发明涉及一种制造光学活性薄荷醇的方法,包括以下步骤:A-1)不对称地氢化
香叶醇和醛中的至少一种,从而得到光学活性
香茅醛;B-1)在酸催化剂存在下对光学活性
香茅醛进行闭环反应,从而得到光学活性
异丁烯二酸;C-1)氢化光学活性
异丁烯二酸,从而得到光学活性薄荷醇。