2-Methylundecanal (CAS 110-41-8) — Musky Base Note Fragrance Ingredient
2-Methylundecanal
CAS 110-41-8
What Is 2-Methylundecanal?
2-Methylundecanal is a synthetic fragrance ingredient with a powerful, animalic musk scent. You’ll find it in perfumes, especially those aiming for sensual or luxurious effects. This molecule matters because it creates depth in fragrances, acting like an invisible velvet curtain that makes floral and citrus notes seem richer and more mysterious.
Safety Profile
GENERALLY SAFEWhat Does 2-Methylundecanal Smell Like?
2-Methylundecanal bursts with an initial waxy, aldehydic sharpness that quickly unfolds into a complex animalic character – imagine warm human skin after a day in the sun, blended with the faintest hint of a beeswax candle. The dry-down reveals a velvety musk that lingers close to the skin, creating an intimate sillage. Over hours, it transforms into something resembling fine leather left in a cedar wardrobe, with just a whisper of dried citrus peel.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Used as a modifier to give depth to the famous aldehyde bouquet, adding a sensual skin-like quality that balances the sparkling top notes.
Amplifies the animalic musk core, creating a provocative, almost feral quality that makes this fragrance legendary.
Provides the warm, human-like musk that blends with lavender and vanilla to create this groundbreaking oriental fougère.
Contributes to the controversial urinous facet that makes this masculine classic so distinctive and polarizing.
Adds a subtle animalic warmth to the vanilla-amber base, creating the ‘skin but better’ effect that defines this oriental.
2D Molecular Structure
SMILES: CCCCCCCCCC(C)C=O
Chemistry, Properties & Perfumer Guide
The Chemistry
2-Methylundecanal is a branched-chain aldehyde with the molecular formula C12H24O. As a synthetic molecule, it’s typically produced through hydroformylation of 2-methylundecene followed by oxidation. The methyl group at the 2-position creates steric hindrance that affects both its odor characteristics and chemical reactivity. It’s part of the C12 aldehyde family, similar to lauric aldehyde but with distinct olfactory properties due to its branching. The molecule’s relatively high molecular weight contributes to its persistence on skin.
Physical & Chemical Properties
| Boiling Point | 232-234 °C |
|---|---|
| Density | 0.83 g/cm³ |
| Refractive Index | 1.432-1.436 |
| Flash Point | >100 °C |
| Vapor Pressure | 0.003 mmHg at 25°C |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.1-0.5% | Up to 1% | Powerful modifier – use sparingly |
| Soap | 0.01-0.05% | Up to 0.1% | Provides long-lasting musk effect |
| Detergent | 0.001-0.005% | Up to 0.01% | Trace amounts add sophistication |
| Candle | 0.05-0.2% | Up to 0.5% | Enhances wax notes |
Classic Accords
Tip: Dilute to 1% in alcohol before use to better control this potent material.
Alternatives & Comparisons
Less animalic, more floral alternative with similar longevity but cleaner profile.
Floral-aldehydic option when you need similar diffusion without the animalic character.
Straight-chain version with more citrus-wax character and less musk.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
No IFRA restrictions (as of 51st Amendment).
RIFM Assessment
RIFM assessment confirms safe use at current levels in fragrance applications.
Sustainability
As a synthetic material, 2-Methylundecanal has minimal environmental impact in production. Its potency means very small quantities are needed, reducing the overall carbon footprint compared to natural musks. The manufacturing process can utilize renewable feedstocks, and modern catalytic methods have significantly improved atom economy compared to traditional synthesis routes.
Explore 2-Methylundecanal
Browse essential oils and aroma compounds.
Browse on iHerb →Affiliate disclosure: we may earn a small commission at no extra cost to you.
References
- Arctander, S. (1969). Perfume and Flavor Chemicals. Montclair, NJ: Steffen Arctander.
- Burdock, G.A. (2010). Fenaroli’s Handbook of Flavor Ingredients. CRC Press.
- Sell, C. (2006). The Chemistry of Fragrances. Royal Society of Chemistry.
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorIngredient Data Sheet
CAS 110-41-8Physical Properties
| Molecular Weight | 184.32 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 4.9🔬 PubChem |
| Boiling Point | 230.9 °C🔬 EPA CompTox |
| Vapor Pressure | 0.0064 mmHg @ 25°C📊 OPERA |
| Flash Point | 68.5 °C🔬 EPA CompTox |
| Involatility Index | 0.0005💻 Calculated |
| log Kp (skin permeability) | -0.345💻 Calculated |
| SMILES | CCCCCCCCCC(C)C=O🔬 PubChem |
Volatility & Performance
| Fragrance Note | Heart💻 Calculated |
| Volatility Class | Very slow💻 Calculated |
| Persistence Score | 5 / 5💻 Calculated |
Odor & Flavor
| Primary Descriptors | dryfattyfruity• leffingwell |
| Functional Groups | aldehyde💻 RDKit |
| “tenacity. Although often described as "aldehydic" it has much more character than the "Lauric aldehyde" (Dodecanal). Odor descriptions of older date include the term "Orange" and this may be due to the very impure aldehyde marketed until about 1960. Up to 15 or even 20% Methyl nonyl ketone in certain commercial lots would heavily influence the refined odor of the Aldehyde.”📖 Arctander | |
Flavor Notes (Arctander)
| “Dry-fruity taste with Honey-Nut-like notes. The aldehyde finds a little use – in mere traces – in flavor compositions, mainly in Citrus complexes, Honey, Coconut, Apricot, Pineapple, etc. or in fruit blends.”📖 Arctander |
Regulatory Status
| FEMA Number | FEMA 2749⚖️ FEMA GRAS |
| GRAS Status | Generally Recognized as Safe⚖️ FEMA GRAS |
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: DTXSID9047629
Physical Properties
| Molecular Weight | 184.323 g/mol🔬 EPA CompTox |
| Density | 0.827 g/cm^3🔬 EPA CTX |
| Boiling Point | 200.925 °C🔬 EPA CTX |
| Melting Point | 15.397 °C📊 OPERA |
| Flash Point | 85.083 °C🔬 EPA CTX |
| Refractive Index | 1.429 Dimensionless📊 OPERA |
| Molar Volume | 224.312 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 4.903 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 4.903 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 4.903 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5.77 Log10 unitless📊 OPERA |
| Water Solubility | 0 mol/L🔬 EPA CTX |
| Henry's Law Constant | 0.001 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.019 mmHg🔬 EPA CTX |
| Viscosity | 2.808 cP📊 OPERA |
| Surface Tension | 26.882 dyn/cm📊 OPERA |
| Thermal Conductivity | 141.221 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 | 9 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 57.789 cm^3/mol📊 OPERA |
| Polarizability | 22.909 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.
Related Research
- Phenethyl propionate (CAS 122-70-3) — Floral Middle Note Fragrance Ingredient
- Isopulegyl acetate (CAS 57576-09-07) — Green Top Note Fragrance Ingredient
- Cedarwood oil acetylated (CAS 61789-42-2) — Woody Base Note Fragrance Ingredient
- Oxirane, 2-methyl-, polymer with oxirane, hexadecyl ether (CAS 9087-53-0) — Citrus Not applicable Note Fragrance Ingredient
