2,6,8-Trimethylnonan-4-one (CAS 123-18-2) — Woody Base Note Fragrance Ingredient
2,6,8-Trimethylnonan-4-one
CAS 123-18-2
What Is 2,6,8-Trimethylnonan-4-one?
2,6,8-Trimethylnonan-4-one is a synthetic fragrance ingredient used to add woody, musky notes to perfumes. It’s commonly found in masculine colognes and luxury scents. This compound is valued for its ability to enhance longevity and add complexity to fragrance compositions, making it a versatile tool for perfumers.
Safety Profile
USE WITH AWARENESSWhat Does 2,6,8-Trimethylnonan-4-one Smell Like?
2,6,8-Trimethylnonan-4-one offers a rich, woody aroma with musky undertones, reminiscent of aged cedarwood and warm leather. Its scent evolves from a sharp, slightly green top note to a smooth, lingering base that blends seamlessly with other woody and amber ingredients. The dry-down is characterized by a subtle, animalic warmth that adds depth to fragrance compositions.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Used to enhance the woody, musky base notes, providing longevity and depth to this modern masculine fragrance.
Adds a subtle woody complexity to the fresh, spicy accord, balancing the citrus top notes.
2D Molecular Structure
SMILES: CC(C)CC(C)CC(=O)CC(C)C
Chemistry, Properties & Perfumer Guide
The Chemistry
2,6,8-Trimethylnonan-4-one is a synthetic ketone with a branched carbon chain. It belongs to the class of woody-musky fragrance ingredients, often synthesized via alkylation of ketones. Its structure contributes to its volatility and scent profile, making it a valuable material in perfumery.
Physical & Chemical Properties
| Boiling Point | N/A |
|---|---|
| Density | N/A |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 1-3% | Up to 5% | Adds woody depth |
| Personal Care | 0.5-1% | Up to 2% | Used for longevity |
Classic Accords
Tip: Use in small amounts to avoid overpowering other notes.
Alternatives & Comparisons
A more widely used woody-musky alternative with better blending properties and lower sensitization potential.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
No specific IFRA restrictions. General guidelines apply.
EU Allergen Declaration
Not listed as an EU allergen.
RIFM Assessment
RIFM has assessed this ingredient as safe for use in current concentrations.
Sustainability
Synthetic production ensures consistent quality and reduces environmental impact compared to natural extraction. Supply chain considerations focus on efficient synthesis methods.
Explore 2,6,8-Trimethylnonan-4-one
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References
- PubChem Compound Summary for 2,6,8-Trimethylnonan-4-one PubChem
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorIngredient Data Sheet
CAS 123-18-2Physical Properties
| Molecular Weight | 184.32 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 3.8🔬 PubChem |
| Boiling Point | 222 °C🔬 EPA CompTox |
| Vapor Pressure | 0.0617 mmHg @ 25°C📊 OPERA |
| Flash Point | 63.1 °C🔬 EPA CompTox |
| Involatility Index | 0.0049💻 Calculated |
| log Kp (skin permeability) | -1.126💻 Calculated |
| SMILES | CC(C)CC(C)CC(=O)CC(C)C🔬 PubChem |
Volatility & Performance
| Fragrance Note | Heart💻 Calculated |
| Volatility Class | Very slow💻 Calculated |
| Persistence Score | 2.5 / 5💻 Calculated |
Odor & Flavor
| Primary Descriptors | muskywoody• leffingwell |
| Functional Groups | ketone💻 RDKit |
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: DTXSID7026998
Physical Properties
| Molecular Weight | 184.323 g/mol🔬 EPA CompTox |
| Density | 0.808 g/cm^3📊 OPERA |
| Boiling Point | 219.891 °C📊 OPERA |
| Melting Point | -9.148 °C📊 OPERA |
| Flash Point | 83 °C🔬 EPA CTX |
| Refractive Index | 1.425 Dimensionless📊 OPERA |
| Molar Volume | 224.866 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 4.144 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 4.144 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 4.144 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5.77 Log10 unitless📊 OPERA |
| Water Solubility | 0.001 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.114 mmHg📊 OPERA |
| Viscosity | 1.543 cP📊 OPERA |
| Surface Tension | 24.981 dyn/cm📊 OPERA |
| Thermal Conductivity | 124.781 mW/(m*K)📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 17.07 Ų💻 Computed |
| H-Bond Donors | 0 count💻 Computed |
| H-Bond Acceptors | 1 count💻 Computed |
| Rotatable Bonds | 6 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 57.549 cm^3/mol📊 OPERA |
| Polarizability | 22.814 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.
