2-Methyl-2-propanol (CAS 75-65-0) — Woody Not applicable Note Fragrance Ingredient
2-Methyl-2-propanol
CAS 75-65-0
What Is 2-Methyl-2-propanol?
2-Methyl-2-propanol, commonly known as tert-butanol, is a synthetic alcohol primarily used in industrial applications and laboratory settings. While not typically found in consumer products, it may appear in some specialized cleaning agents or chemical formulations. This compound serves as a versatile solvent and intermediate in chemical synthesis, though its direct use in fragrances is limited due to its strong chemical odor and lower volatility compared to other alcohols.
Safety Profile
USE WITH AWARENESSWhat Does 2-Methyl-2-propanol Smell Like?
2-Methyl-2-propanol has a sharp, pungent alcoholic odor with camphoraceous undertones. Its scent is notably harsh and solvent-like, lacking the pleasant nuances of smaller alcohols like ethanol. The odor profile remains linear without significant evolution, persisting with a dry, chemical character that can overwhelm delicate fragrance compositions. In high concentrations, it may impart a medicinal or rubbery off-note.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
This compound is rarely employed in fine fragrance due to its harsh odor profile and limited olfactory appeal. It may appear in trace amounts as a solvent or carrier in some industrial fragrance applications.
2D Molecular Structure
SMILES: CC(C)(C)O
Chemistry, Properties & Perfumer Guide
The Chemistry
2-Methyl-2-propanol is a tertiary alcohol with the formula (CH₃)₃COH. As the simplest tertiary alcohol, it features three methyl groups attached to a central carbon bearing a hydroxyl group. Industrially produced through hydration of isobutene or as a byproduct of MTBE production, its sterically hindered structure gives it distinct chemical properties compared to primary and secondary alcohols. The tertiary carbon center makes it more resistant to oxidation but more prone to elimination reactions.
Physical & Chemical Properties
| Boiling Point | 82-83 °C |
|---|---|
| Melting Point | 25-26 °C |
| Flash Point | 11 °C |
| Density | 0.781 g/cm³ |
| Vapor Pressure | 40 mmHg at 20°C |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Industrial Fragrance | 0-0.1% | Trace amounts | Primarily as solvent/carrier |
| Cleaning Products | 1-5% | Up to 10% | Solvent properties |
Classic Accords
Tip: Avoid in fine fragrance; consider only as solvent in industrial applications where odor is secondary.
Alternatives & Comparisons
Preferred alcohol solvent with milder odor profile and better fragrance compatibility.
More volatile alternative with cleaner evaporation profile for carrier applications.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
No specific IFRA restrictions, but not recommended for fragrance use.
GHS Classification
RIFM Assessment
Not evaluated by RIFM for fragrance use due to limited perfumery applications.
Sustainability
Synthesized from petrochemical feedstocks, 2-methyl-2-propanol has significant environmental impacts in production. Its high volatility contributes to VOC emissions. Sustainable alternatives should be considered where possible. Industrial recycling of this solvent is recommended to minimize environmental release.
Explore 2-Methyl-2-propanol
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 for 2-Methyl-2-propanol CID 6386
- OECD SIDS Initial Assessment Report for tert-Butanol OECD SIDS
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorIngredient Data Sheet
CAS 75-65-0Physical Properties
| Molecular Weight | 74.12 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 0.5🔬 PubChem |
| Boiling Point | 82.2 °C🔬 EPA CompTox |
| Vapor Pressure | 31 mmHg @ 25°C📊 OPERA |
| Flash Point | 11.1 °C🔬 EPA CompTox |
| Involatility Index | 3.8808💻 Calculated |
| log Kp (skin permeability) | -2.797💻 Calculated |
| SMILES | CC(C)(C)O🔬 PubChem |
Volatility & Performance
| Fragrance Note | Top💻 Calculated |
| Volatility Class | Very fast💻 Calculated |
| Persistence Score | 0.5 / 5💻 Calculated |
Odor & Flavor
| Primary Descriptors | ethereal• leffingwell |
| Functional Groups | alcohol💻 RDKit |
| “Camphoraceous and somewhat "minty" odor, the dryness being characteristic and different from the other isomers.”📖 Arctander | |
Sensory Thresholds
| Odor Detection Threshold | 33.7524 ppm (n=17)📖 van Gemert |
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: DTXSID8020204
Physical Properties
| Molecular Weight | 74.123 g/mol🔬 EPA CompTox |
| Density | 0.788 g/cm^3🔬 EPA CTX |
| Boiling Point | 82.49 °C🔬 EPA CTX |
| Melting Point | 25.515 °C🔬 EPA CTX |
| Flash Point | 11.408 °C🔬 EPA CTX |
| Refractive Index | 1.395 Dimensionless📊 OPERA |
| Molar Volume | 92.117 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 0.434 Log10 unitless🔬 EPA CTX |
| LogD (pH 5.5) | 0.537 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 0.537 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 3.5 Log10 unitless🔬 EPA CTX |
| Water Solubility | 10.297 mol/L🔬 EPA CTX |
| Henry's Law Constant | 0 atm-m3/mole🔬 EPA CTX |
Transport Properties
| Vapor Pressure | 41.436 mmHg🔬 EPA CTX |
| Viscosity | 2.038 cP📊 OPERA |
| Surface Tension | 23.035 dyn/cm📊 OPERA |
| Thermal Conductivity | 143.24 mW/(m*K)📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 20.23 Ų💻 Computed |
| H-Bond Donors | 1 count💻 Computed |
| H-Bond Acceptors | 1 count💻 Computed |
| Rotatable Bonds | 0 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 22.081 cm^3/mol📊 OPERA |
| Polarizability | 8.754 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
- Spearmint oil, 60% (CAS 91770-24-0) — Green Top to middle Note Fragrance Ingredient
- 2-Methylpentanal (CAS 123-15-9) — Green Top Note Fragrance Ingredient
- 3-Methyl-2-(pentyloxy)cyclopent-2-en-1-one (CAS 68922-13-4) — Woody Middle Note Fragrance Ingredient
- Methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (CAS 6386-38-5) — Woody N/A Note Fragrance Ingredient
