August 24, 2025 | UR Gate
Menthol (C10H20O) Structure, Properties and Nomenclature
Discover Menthol (C10H20O), a cyclic terpene alcohol found in mint plants. Learn its structure, key properties, IUPAC name, synonyms, and its cooling sensation, use in flavorings, fragrances, and topical analgesics.
What is Menthol (C10H20O)?
Menthol is a cyclic terpene alcohol that is a key component of peppermint oil and other mint oils. It is renowned for its characteristic cooling sensation and refreshing minty aroma, making it a popular ingredient in a wide array of products. These include confectionery, chewing gum, toothpaste, mouthwash, cigarettes, and topical analgesics like balms and lotions, where it provides a soothing and cooling effect. Menthol exists as several stereoisomers, with (-)-menthol (or L-menthol) being the most abundant and commercially significant due to its strong cooling properties and distinct aroma. Its structure, a saturated cyclohexane ring with a hydroxyl group and an isopropyl group, is responsible for its unique sensory effects.
Properties of Menthol (C10H20O)
| Property | Value |
|---|---|
| Molecular Formula | C₁₀H₂₀O |
| Molecular Weight | 156.27 g/mol |
| Density | 0.890 g/cm³ (at 25°C for L-menthol) |
| Boiling Point | 212 °C (for L-menthol) |
| Melting Point | 41–44 °C (for L-menthol) |
| Hybridization | All carbon atoms are sp³ hybridized. |
| Appearance | White or colorless crystalline solid |
| Solubility | Slightly soluble in water; very soluble in organic solvents such as ethanol, ether, and chloroform. |
Nomenclature of Menthol
- Common name: Menthol
- IUPAC name: (1R,2S,5R)-2-isopropyl-5-methylcyclohexanol (for L-menthol)
Synonyms
- L-Menthol
- (-)-Menthol
- (–)-Menthol
- 2-Isopropyl-5-methylcyclohexanol
- Peppermint camphor
- (1R,3R,4S)-(-)-Menthol
