Isophorol (CAS 470-99-5) — Woody Heart to Base Note Fragrance Ingredient

ByThe Good Scents
Woody · Balsamic

Isophorol

CAS 470-99-5

Origin
synthetic
Note
Heart to Base
IFRA
Generally safe
Data as of: Apr 2026

What Is Isophorol?

Isophorol is a synthetic fragrance ingredient used to add woody, balsamic notes to perfumes and personal care products. You might encounter it in aftershaves, colognes, or home fragrances where a masculine, resinous character is desired. This molecule is valued for its ability to blend well with other woody and spicy notes, creating depth and longevity in fragrance compositions. It acts as a versatile building block that perfumers use to craft complex accords with natural characteristics.

Safety Profile

GENERALLY SAFE
Generally safeUse with awarenessProfessional use
✓ No major safety concerns at typical usage levels
⚠ Limited toxicity data available
CAS
470-99-5
Formula
Mixture
MW
Variable
Odor Family
Woody · Balsamic
Layer 1 · Enthusiast

What Does Isophorol Smell Like?

Isophorol presents a rich, woody-balsamic character with subtle camphoraceous undertones. The initial impression is reminiscent of aged cedarwood with a faintly medicinal edge, like the inside of an antique apothecary cabinet. As it develops, the aroma reveals a warm, slightly sweet resinous quality similar to pine sap or frankincense. The dry-down maintains a persistent woody backbone with a clean, almost soapy finish that makes it useful for masculine fougère compositions. Its moderate volatility ensures it contributes to both the heart and base stages of a fragrance.

Scent Profile
Layer 2

2D Molecular Structure

3,5,5-Trimethyl-2-cyclohexen-1-ol

SMILES: CC1=CC(O)CC(C)(C)C1

Chemistry, Properties & Perfumer Guide

The Chemistry

Isophorol is a bicyclic tertiary alcohol belonging to the terpenoid family, though it’s produced synthetically rather than extracted from natural sources. The molecule features a complex three-dimensional structure that contributes to its distinctive odor profile. Industrial synthesis typically involves catalytic hydrogenation of isophorone, a process that creates this stable, versatile fragrance intermediate. While not chiral itself, isophorol’s rigid structure gives it excellent fixative properties in perfume formulations.

Physical & Chemical Properties

Perfumer Guide

Note Position
Heart to Base
Volatility
Moderate (2-6 hours)
Blending
Good
ApplicationTypical %RangeNotes
Fine Fragrance1-3%Up to 5%Woody modifier
Personal Care0.5-1%Up to 2%Adds masculine character
Home Fragrance2-5%Up to 8%Balsamic base note

Classic Accords

Tip: Use isophorol to add woody depth without overwhelming the composition – it works particularly well in amber and fougère bases.

Alternatives & Comparisons

1
Isobornyl cyclohexanol CAS 707-35-7

Offers similar woody characteristics with slightly more floral nuance and better stability in alkaline formulations.

2
Cedrol CAS 77-53-2

Natural alternative with comparable woody profile but higher cost and lower solubility in alcohol bases.

Layer 3

Safety, Regulatory & Sustainability

⚠ Regulatory Disclaimer

General reference only. Consult current IFRA Standards Library before formulating.

IFRA Status

Not currently restricted by IFRA standards.

RIFM Assessment

RIFM has not published a full safety assessment for isophorol as of current data.

Sustainability

As a synthetic material, isophorol’s production doesn’t rely on natural resource extraction. However, its synthesis from petrochemical feedstocks carries typical environmental impacts of industrial chemistry. Some manufacturers are exploring bio-based routes to similar molecules, though these alternatives have not yet matched isophorol’s cost-performance balance in fragrance applications.

Explore Isophorol

Browse essential oils and aroma compounds.

Browse on iHerb →

Affiliate disclosure: we may earn a small commission at no extra cost to you.

References

    Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.

    Report a data error

    Perfumer’s Notes

    MW: 140.22

    LogP: 1.7

    Ingredient Data Sheet

    CAS 470-99-5

    Physical Properties

    Molecular Weight140.22 g/mol🔬 PubChem
    LogP (Octanol-Water)1.7🔬 PubChem
    Boiling Point218 °C🔬 EPA CompTox
    Vapor Pressure0.4467 mmHg @ 25°C📊 OPERA
    Flash Point80 °C🔬 EPA CompTox
    Involatility Index0.0407💻 Calculated
    log Kp (skin permeability)-2.348💻 Calculated
    SMILESCC1=CC(CC(C1)(C)C)O🔬 PubChem

    Volatility & Performance

    Fragrance NoteTop💻 Calculated
    Volatility ClassSlow💻 Calculated
    Persistence Score0.5 / 5💻 Calculated

    Odor & Flavor

    Functional Groupsalcoholalkene💻 RDKit
    “Warm and sweet-herbaceous, honey-like odor. Although the odor does resemble that of iso-Phorone (see next) to a minor degree, it is much softer and sweeter, and does not have the harsh, pungent and aggressive topnote as found in iso-Phorone.”📖 Arctander
    Data Sources & Attribution
    Physical data: PubChem (NIH/NLM), U.S. EPA CompTox Dashboard, EPA OPERA models, RDKit. Odor & flavor: Arctander (Perfume & Flavor Chemicals), Fenaroli's Handbook of Flavor Ingredients, Leffingwell. Thresholds: van Gemert (Compilations of Odour Threshold Values). Regulatory: IFRA Standards 51st, FEMA GRAS. Trade names: Surburg (Common Fragrance & Flavor Materials). All data compiled and cross-referenced for perfumertools.com.

    Physicochemical Properties

    DTXSID: DTXSID6047072

    Physical Properties

    Molecular Weight 140.226 g/mol🔬 EPA CompTox
    Density 0.91 g/cm^3🔬 EPA CTX
    Boiling Point 203.356 °C📊 OPERA
    Melting Point 25.798 °C📊 OPERA
    Flash Point 77.916 °C📊 OPERA
    Refractive Index 1.472 Dimensionless📊 OPERA
    Molar Volume 153.133 cm^3/mol📊 OPERA

    Partition & Solubility

    LogP (Octanol-Water) 2.802 Log10 unitless📊 OPERA
    LogD (pH 5.5) 2.802 Log10 unitless📊 OPERA
    LogD (pH 7.4) 2.802 Log10 unitless📊 OPERA
    LogKoa (Octanol-Air) 6.09 Log10 unitless📊 OPERA
    Water Solubility 0.028 mol/L📊 OPERA
    Henry's Law Constant 0 atm-m3/mole📊 OPERA

    Transport Properties

    Vapor Pressure 0.253 mmHg📊 OPERA
    Viscosity 7.642 cP📊 OPERA
    Surface Tension 29.112 dyn/cm📊 OPERA
    Thermal Conductivity 128.867 mW/(m*K)📊 OPERA

    Molecular Descriptors

    Topological Polar Surface Area 20.23 Ų💻 Computed
    H-Bond Donors 1 count💻 Computed
    H-Bond Acceptors 1 count💻 Computed
    Rotatable Bonds 0 count💻 Computed
    Aromatic Rings 0 count💻 Computed
    Molar Refractivity 42.89 cm^3/mol📊 OPERA
    Polarizability 17.003 Å^3📊 OPERA

    Data Sources:

    🔬 EPA Experimental data from U.S. EPA CompTox Chemicals Dashboard & CTX APIs. 📊 OPERA Predicted using EPA's OPERA QSAR models. 💻 Computed Calculated from SMILES using RDKit.

    Similar Posts