Citronellol
| Category | TERPENES |
| Subcategory | monoterpenoid · alcohol · rose-type |
| Origin | |
| Volatility | Heart-Top Note |
| Botanical | 3,7-Dimethyloct-6-en-1-ol |
| Appearance | Colourless to pale yellow liquid |
| Odor Strength | Medium |
| Producing Countries | China (synthetic), India (geranium oil), Egypt (geranium), Reunion (geranium) |
| Pyramid | Heart-Top |
A naturally occurring monoterpenoid alcohol with a green, rosy, citrusy odour. One of the primary components of rose otto (15–40%) and geranium oil (25–45%). Widely used in perfumery as a building block in rose accords and fresh-floral compositions. An EU-listed allergen requiring mandatory declaration on cosmetic labels above 0.001% in leave-on products.
- Scent
- The Full Story
- Extraction & Chemistry
- In Perfumery
Scent
Opening: fresh, green-rosy, slightly citrusy. A clean floral with a transparent quality. Less dense than geraniol, less sweet than linalool.
Development: the rosy character intensifies as the green-citrus top fades. On a smelling strip, the rose quality becomes dominant after 30 minutes.
Dry-down: clean, faintly waxy, with residual green tones. Low substantivity — citronellol is among the more volatile of the common terpenoid alcohols.
The Full Story
Citronellol exists as two enantiomers. (+)-Citronellol (R-form) predominates in citronell a oil and has a slightly harsher, more citrusy character. (−)-Citronellol (S-form, also called rhodinol) predominates in rose otto and Bourb on geranium oil, contributing the softer, rosy quality. Commercial citronellol is usually a racemic mixture or enriched in one enantiomer depending on the source.
This note in Première Peau. Sample all seven extraits in the Discovery Set.
In nature, citronellol occurs at significant concentrations in Rosa damascena (15–40% of the essential oil), Pelargonium graveolens (geranium, 25–45%), and Cymbopogon nardus (citronella, 5–15%). It is also found in smaller quantities in lemongrass, eucalyptus citriodora, and certain basil chemotypes.
Industrial production uses either isolation from natural oils (primarily Bourbon geranium) or catalytic hydrogenation of geraniol or nerol. Synthetic citronellol is chemically identical to the natural molecule.
Citronellol is classified as a fragrance allergen under EU Cosmetic Regulation (EC) No 1223/2009 and must be declared on ingredient labels when present above threshold concentrations (0.001% in leave-on products, 0.01% in rinse-off). This does not prohibit its use — it requires transparency.
| Molecular Formula | C₁₀H₂₀O |
| CAS Number | 106-22-9 |
| Botanical Name | 3,7-Dimethyloct-6-en-1-ol |
| IFRA Status | EU allergen — declaration required above 0.001% (leave-on) / 0.01% (rinse-off) |
| Synonyms | β-CITRONELLOL · DIHYDROGERANIOL · CEPHROL |
In Perfumery
Citronellol is a workhorse in rose reconstructi on. It provides the fresh, green-rosy top of a rose accord, complementing geraniol (which provides the sweeter, honeyed quality) and phenylethyl alcohol (which contributes the heavier, deeper rose petal quality). Used extensively in fresh florals, green compositions, and as a natural modifier to add transparency to heavier bases. Annual global consumpti on in fragrance exceeds 3,000 tonnes.
