2-Methylbutyl hexanoate (CAS 2601-13-0) — Sweet Top Note Fragrance Ingredient
2-Methylbutyl hexanoate
CAS 2601-13-0
What Is 2-Methylbutyl hexanoate?
2-Methylbutyl hexanoate is a synthetic fruity ester commonly found in food flavorings and some perfumes. It delivers a ripe, juicy apple-pear character. This ingredient matters because it provides realistic top notes in fragrances while being more stable than natural fruit extracts, making scents last longer without discoloration.
Safety Profile
GENERALLY SAFEWhat Does 2-Methylbutyl hexanoate Smell Like?
A burst of overripe orchard fruits – imagine biting into a sun-warmed pear with a drop of apple brandy. The initial intensity mellows into a candied peel effect, leaving a faint waxy-green trail like fruit stems. Unlike simpler esters, the branched chain adds dimensionality that prevents cloying sweetness.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Provides a crisp fruity lift to contrast the animalic base. The methyl branching prevents interference with the honeyed tobacco accord.
Used sparingly to enhance the citrus top with a photorealistic apple nuance that bridges to floral heart notes.
2D Molecular Structure
SMILES: CCCCCC(=O)OCC(C)CC
Chemistry, Properties & Perfumer Guide
The Chemistry
A branched-chain ester formed via Fischer esterification of 2-methyl-1-butanol with hexanoic acid. The β-branching creates steric hindrance that slows hydrolysis compared to linear esters. Industrial production typically uses acid catalysis at 60-80°C. Chiral versions exist but commercial material is racemic.
Physical & Chemical Properties
| Boiling Point | 198 °C |
|---|---|
| Density | 0.865 g/cm³ |
| Refractive Index | 1.415-1.420 |
| Flash Point | 78 °C |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.5-2% | Up to 5% | Fruity modifier |
| Functional Fragrance | 0.1-0.5% | Up to 1% | Soap/detergent stability |
Classic Accords
Tip: Use with citrus or green notes to prevent excessive sweetness.
Alternatives & Comparisons
Linear version with cleaner pear character but less diffusion. Better for aquatic applications.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
No restrictions under IFRA Standards.
RIFM Assessment
RIFM-reviewed with no identified safety concerns at current usage levels.
Sustainability
Synthesized from petrochemical feedstocks but with high atom economy. Biodegradation studies show >90% breakdown in 28 days. No known ecological toxicity at fragrance use levels.
Explore 2-Methylbutyl hexanoate
Browse essential oils and aroma compounds.
Browse on iHerb →Affiliate disclosure: we may earn a small commission at no extra cost to you.
References
- Burdock, G.A. (2010). Fenaroli’s Handbook of Flavor Ingredients. CRC Press. ISBN 9781420090772
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorPhysicochemical Properties
DTXSID: DTXSID30862996
Physical Properties
| Molecular Weight | 186.295 g/mol🔬 EPA CompTox |
| Density | 0.867 g/cm^3📊 OPERA |
| Boiling Point | 214.958 °C📊 OPERA |
| Melting Point | -53.92 °C📊 OPERA |
| Flash Point | 81.813 °C📊 OPERA |
| Refractive Index | 1.425 Dimensionless📊 OPERA |
| Molar Volume | 213.969 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 4.152 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 4.152 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 4.152 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5.56 Log10 unitless📊 OPERA |
| Water Solubility | 0.001 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.168 mmHg📊 OPERA |
| Viscosity | 1.602 cP📊 OPERA |
| Surface Tension | 26.784 dyn/cm📊 OPERA |
| Thermal Conductivity | 135.083 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 | 7 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 54.744 cm^3/mol📊 OPERA |
| Polarizability | 21.702 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.
