Ethyl 2-mercaptopropionate (CAS 19788-49-9) — Sweet Top to middle Note Fragrance Ingredient
Ethyl 2-mercaptopropionate
CAS 19788-49-9
What Is Ethyl 2-mercaptopropionate?
Ethyl 2-mercaptopropionate is a synthetic fragrance ingredient used to add fruity, tropical nuances to perfumes. It’s found in some modern citrus and exotic fruit-themed fragrances. This ingredient matters because it can mimic natural fruit aromas at lower costs, though its sulfur-containing structure requires careful formulation to avoid overpowering compositions.
Safety Profile
USE WITH AWARENESSWhat Does Ethyl 2-mercaptopropionate Smell Like?
Ethyl 2-mercaptopropionate bursts with intense tropical fruitiness – imagine overripe pineapple blending with passionfruit nectar. The initial sulfurous punch quickly mellows into a juicy, slightly creamy sweetness reminiscent of guava puree. As it dries down, it maintains a persistent candied fruit character with subtle green undertones, behaving like a more tenacious version of ethyl maltol.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Used for its sun-kissed tropical fruit effect, enhancing the coconut-citrus accord while adding depth to the white floral heart.
Provides the cocktail-like lime and rum top notes with extra juicy dimensionality and tropical authenticity.
2D Molecular Structure
SMILES: CCOC(=O)C(C)S
Chemistry, Properties & Perfumer Guide
The Chemistry
This ester combines a thiol group with propionic acid, creating its characteristic sulfurous fruit profile. Synthesized through esterification of 2-mercaptopropionic acid with ethanol, its reactivity requires careful handling. The molecule’s chirality influences its odor profile, with the (R)-enantiomer being more intensely fruity.
Physical & Chemical Properties
| Molecular Weight | 134.18 g/mol |
|---|---|
| Boiling Point | 198-200 °C |
| Density | 1.053 g/cm³ (20 °C) |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.1-0.5% | Up to 1% | Use sparingly due to potency |
| Functional Fragrance | 0.01-0.1% | Up to 0.3% | For tropical fruit shower gels |
Classic Accords
Tip: Counterbalance sulfur notes with ionones or vanillin derivatives.
Alternatives & Comparisons
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
Not currently restricted under IFRA standards.
EU Allergen Declaration
Not listed in EU allergen regulation.
GHS Classification
RIFM Assessment
RIFM evaluation ongoing – recommended use levels under review.
Sustainability
Synthesized from petrochemical feedstocks, though newer green chemistry routes using bio-based ethanol are being explored. The sulfur content requires careful waste stream management during production.
Explore Ethyl 2-mercaptopropionate
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.
- Arctander, S. (1969). Perfume and Flavor Chemicals. Allured Publishing.
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorPhysicochemical Properties
DTXSID: DTXSID20864904
Physical Properties
| Molecular Weight | 134.19 g/mol🔬 EPA CompTox |
| Density | 1.039 g/cm^3🔬 EPA CTX |
| Boiling Point | 173.209 °C📊 OPERA |
| Melting Point | -19.104 °C📊 OPERA |
| Flash Point | 48.689 °C📊 OPERA |
| Refractive Index | 1.453 Dimensionless📊 OPERA |
| Molar Volume | 128.976 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 1.241 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 1.236 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 1.078 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 3.65 Log10 unitless📊 OPERA |
| Water Solubility | 0.092 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 1.231 mmHg📊 OPERA |
| Viscosity | 0.966 cP📊 OPERA |
| Surface Tension | 29.161 dyn/cm📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 26.3 Ų💻 Computed |
| H-Bond Donors | 1 count💻 Computed |
| H-Bond Acceptors | 3 count💻 Computed |
| Rotatable Bonds | 2 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 34.843 cm^3/mol📊 OPERA |
| Polarizability | 13.813 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.
![Pentanedioic acid, 1-(4-formyl-2-methoxyphenyl) 5-[(1R,2S,5R)-5-methyl-2-(1-methylethyl)cyclohexyl] ester (CAS 2308574-23-2) — Woody Heart to base Note Fragrance Ingredient](https://thegoodscents.company/wp-content/uploads/2026/04/pentanedioic-acid-1-1-1-768x439.webp)
![Formic acid, reaction products with boron trifluoride and [1S-(1,3a,4,8a)]-decahydro-4,8,8-trimethyl-9-methylene-1,4-methanoazulene (CAS 68855-38-9) — Woody Base Note Fragrance Ingredient](https://thegoodscents.company/wp-content/uploads/2026/04/formic-acid-reaction-products-with-boron-trifluoride-and-1s-1-1-768x439.webp)
