OPTICALLY ACTIVE 4-HYDROXY-1-P-MENTHENE

摘要

PURPOSE: To obtain the subject compound capable of giving fragrance and taste like a natural citron or fragrance and taste like fresh citrus accompanying peel feeling and bitter taste characteristic to pericarp and juice of a citrus. CONSTITUTION: This is ah optically active 4-hydroxy-1-p-menthene of the formula (R1 is methyl or formyl; R2 is H or O; when R1 is methyl, R2 is O and when R1 is formyl, R2 is H), e.g. (4S)-(+)-4--hydroxy-1-p-menthene-6-one (A) or (4 R)-(-)-4-hydroxy-1-p-menthene-7-al (B). The compound of the formula is easily obtained by catalytic oxidation of e.g. (-)-terpinene-4-ol in the presence of selenium dioxide in an organic solvent. The compound A has citrus-like fragrance and taste accompanying peel feeling and bitter taste like thymol. The compound B has citrus-like fragrance and taste accompanying peel feeling and dry woody feeling.