2-Nonenoic acid gamma-lactone (CAS 21963-26-8) — Sweet Middle Note Fragrance Ingredient
2-Nonenoic acid gamma-lactone
CAS 21963-26-8
What Is 2-Nonenoic acid gamma-lactone?
2-Nonenoic acid gamma-lactone is a synthetic fragrance ingredient used to create creamy, coconut-like nuances in perfumes and flavored products. It’s found in tropical-inspired body lotions, suntan oils, and gourmand fragrances. This lactone matters because it provides authentic dairy notes without animal-derived ingredients, making it vegan-friendly while offering superior stability in formulations compared to natural dairy lactones.
Safety Profile
GENERALLY SAFEWhat Does 2-Nonenoic acid gamma-lactone Smell Like?
Opens with a burst of warm, fatty creaminess reminiscent of fresh coconut milk spilling over ripe peaches. The heart develops into a rich, buttery accord with nuances of toasted hazelnuts and condensed milk. Dry-down reveals a soft, musky undertone that lingers like the memory of tropical suntan oil on warm skin. Exceptionally tenacious for a lactone, it behaves more like a base note despite its medium molecular weight.
2D Molecular Structure
SMILES: CCCCCC1OC(=O)C=C1
Chemistry, Properties & Perfumer Guide
The Chemistry
2-Nonenoic acid gamma-lactone belongs to the γ-lactone family, characterized by a five-membered ring containing an ester group. Unlike natural δ-lactones found in dairy, this synthetic variant offers superior oxidative stability. Industrially produced via esterification of 2-nonenoic acid followed by intramolecular cyclization. The trans-configuration of the double bond at position 2 enhances both volatility and olfactive impact compared to saturated analogs.
Physical & Chemical Properties
| Boiling Point | Not available |
|---|---|
| Density | Not available |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.5-2% | Up to 5% | Creamy modifier |
| Body Care | 0.1-1% | Up to 3% | Suntan oil effects |
| Flavors | 10-50 ppm | Up to 100 ppm | Dairy replacer |
Classic Accords
Tip: Pair with ionones to create photorealistic suntan oil effects.
Alternatives & Comparisons
Natural coconut lactone with shorter longevity but greater top note impact.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
Not currently restricted by IFRA.
RIFM Assessment
No RIFM safety assessment found as of 2023.
Sustainability
Synthetic production avoids agricultural land use and seasonal variability. The petrochemical origin raises carbon footprint concerns, but modern manufacturing achieves 85% atom efficiency. Future routes may use bio-based 2-nonenoic acid from oleochemical feedstocks.
Explore 2-Nonenoic acid gamma-lactone
Browse essential oils and aroma compounds.
Browse on iHerb →Affiliate disclosure: we may earn a small commission at no extra cost to you.
References
- PubChem Compound Summary CID 21963-26-8 PubChem
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorIngredient Data Sheet
CAS 21963-26-8Physical Properties
| Molecular Weight | 154.21 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 2.6🔬 PubChem |
| Boiling Point | 207 °C🔬 EPA CompTox |
| Vapor Pressure | 0.0501 mmHg @ 25°C📊 OPERA |
| Flash Point | 111.1 °C🔬 EPA CompTox |
| Involatility Index | 0.0043💻 Calculated |
| log Kp (skin permeability) | -1.795💻 Calculated |
| SMILES | CCCCCC1C=CC(=O)O1🔬 PubChem |
Volatility & Performance
| Fragrance Note | Heart💻 Calculated |
| Volatility Class | Very slow💻 Calculated |
| Persistence Score | 2.1 / 5💻 Calculated |
Odor & Flavor
| Primary Descriptors | coconutcoumarinicfattyhay• leffingwell |
| Functional Groups | esteretheralkene💻 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: DTXSID70865022
Physical Properties
| Molecular Weight | 154.209 g/mol🔬 EPA CompTox |
| Density | 0.987 g/cm^3📊 OPERA |
| Boiling Point | 243.744 °C📊 OPERA |
| Melting Point | -3.911 °C📊 OPERA |
| Flash Point | 109.127 °C📊 OPERA |
| Refractive Index | 1.461 Dimensionless📊 OPERA |
| Molar Volume | 156.642 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 2.449 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 2.449 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 2.449 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5.78 Log10 unitless📊 OPERA |
| Water Solubility | 0.018 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.021 mmHg📊 OPERA |
| Viscosity | 2.114 cP📊 OPERA |
| Surface Tension | 31.801 dyn/cm📊 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 | 4 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 43.012 cm^3/mol📊 OPERA |
| Polarizability | 17.051 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.
