Butyl 10-undecenoate (CAS 109-42-2) — Sweet Top Note Fragrance Ingredient
Butyl 10-undecenoate
CAS 109-42-2
What Is Butyl 10-undecenoate?
Butyl 10-undecenoate is a synthetic ester used in perfumery for its fruity, floral, and slightly green aroma. It’s commonly found in personal care products and air fresheners. This ingredient matters because it adds a fresh, uplifting character to fragrances, making it popular in spring and summer scents.
Safety Profile
GENERALLY SAFEWhat Does Butyl 10-undecenoate Smell Like?
Butyl 10-undecenoate offers a bright, fruity aroma reminiscent of ripe pears and green apples, with a subtle floral undertone. The scent evolves from a sharp, green top note to a softer, more rounded fruity heart, and finally settles into a delicate, slightly sweet dry-down. Its behavior is linear but pleasant, making it a versatile choice for fresh fragrances.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Used for its crisp, fruity top note that blends seamlessly with citrus and floral accords, creating a refreshing morning scent.
Adds a green, slightly tart edge to the fruity heart, enhancing the overall freshness of the composition.
2D Molecular Structure
SMILES: CCCCOC(=O)CCCCCCCCC=C
Chemistry, Properties & Perfumer Guide
The Chemistry
Butyl 10-undecenoate is an ester formed from butanol and 10-undecenoic acid. It is typically synthesized via esterification in the presence of an acid catalyst. The compound is valued for its stability and consistent olfactory profile, making it a reliable choice for perfumers.
Physical & Chemical Properties
| Boiling Point | Not available |
|---|---|
| Density | Not available |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 1-5% | Up to 10% | Adds fruity freshness |
| Personal Care | 0.5-3% | Up to 5% | Light, uplifting note |
Classic Accords
Tip: Use in small amounts to avoid overpowering the composition.
Alternatives & Comparisons
Offers a similar fruity note but with a more pronounced apple-like character.
Provides a smoother, less green fruity note with better longevity.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
No restrictions under IFRA standards.
EU Allergen Declaration
Not listed as an EU allergen.
RIFM Assessment
No significant safety concerns identified by RIFM.
Sustainability
Butyl 10-undecenoate is synthesized from petrochemical sources, making its environmental impact dependent on industrial processes. Efforts to use renewable feedstocks for similar esters are ongoing.
Explore Butyl 10-undecenoate
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References
- PubChem: Butyl 10-undecenoate PubChem
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorIngredient Data Sheet
CAS 109-42-2Physical Properties
| Molecular Weight | 240.38 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 5.5🔬 PubChem |
| Boiling Point | 249 °C🔬 EPA CompTox |
| log Kp (skin permeability) | -0.261💻 Calculated |
| SMILES | CCCCOC(=O)CCCCCCCCC=C🔬 PubChem |
Volatility & Performance
| Fragrance Note | Heart💻 Calculated |
Odor & Flavor
| Primary Descriptors | butteryfattywaxy• leffingwell |
| Functional Groups | esteretheralkene💻 RDKit |
| Butyl 10-undecenoate has a slightly fatty, buttery, wine-like, unpleasant odor.📖 Fenaroli | |
Regulatory Status
| IOFI Classification | Artificial📖 Fenaroli |
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: DTXSID4047624
Physical Properties
| Molecular Weight | 240.387 g/mol🔬 EPA CompTox |
| Density | 0.866 g/cm^3📊 OPERA |
| Boiling Point | 251.5 °C🔬 EPA CTX |
| Melting Point | -24.649 °C📊 OPERA |
| Flash Point | 123.242 °C📊 OPERA |
| Refractive Index | 1.444 Dimensionless📊 OPERA |
| Molar Volume | 274.712 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 5.714 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 5.714 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 5.714 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 7.51 Log10 unitless📊 OPERA |
| Water Solubility | 0 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.001 mmHg📊 OPERA |
| Viscosity | 3.478 cP📊 OPERA |
| Surface Tension | 29.213 dyn/cm📊 OPERA |
| Thermal Conductivity | 145.962 mW/(m*K)📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 26.3 Ų💻 Computed |
| H-Bond Donors | 0 count💻 Computed |
| H-Bond Acceptors | 2 count💻 Computed |
| Rotatable Bonds | 12 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 73.042 cm^3/mol📊 OPERA |
| Polarizability | 28.956 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.
