Studies on Menthol Derivatives

Part I. Synthesis of (-)-Menthyl Carbinol

Abstract

(-)-Menthyl carbinol (1-(R)-Methly-3-(R)-hydroxymethyl-4-(S)-isopropylcyclohexane) (4) was prepared stereospecifically in good yield by treatment of formaldehyde with the Grignard reagent from (-)-menthyl chloride (2), which was prepared from (-)-menthol-(1-(R)-methyl-3-(R)-hydroxy-4-(S)-isopropylcyclohexane) (1) by chorination using the Lucas reagent (HCl+ZnCl₂). The configuration of 4 was assigned by the chemical method.