4-Methyl-2-pentylpyridine (CAS 84625-54-7) — Musky Middle to base Note Fragrance Ingredient
4-Methyl-2-pentylpyridine
CAS 84625-54-7
What Is 4-Methyl-2-pentylpyridine?
4-Methyl-2-pentylpyridine is a synthetic aroma chemical used in perfumery to create unique olfactory effects. You might encounter it in niche fragrances where its distinctive character adds depth and complexity. This ingredient matters because it offers perfumers a tool to craft unconventional scent profiles, often contributing to modern, avant-garde compositions that stand out from traditional floral or citrus fragrances.
Safety Profile
USE WITH AWARENESSWhat Does 4-Methyl-2-pentylpyridine Smell Like?
4-Methyl-2-pentylpyridine presents a sharp, pungent aroma with distinct pyridine character – imagine the electric tang of hot metal meeting the green bite of unripe tomatoes. Its opening is aggressively chemical, settling into a leathery-animalic heart with hints of burnt rubber and tobacco. The dry-down reveals surprising warmth, like a smoldering campfire doused with motor oil, leaving an addictive industrial edge that lingers on skin for hours.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Used here to create the scorched metal accord that contrasts with traditional barbershop notes, embodying the fragrance’s concept of a barbershop on fire.
Provides the asphalt-like roughness that supports the dark tobacco and cannabis notes, adding an urban edge to this controversial fragrance.
2D Molecular Structure
SMILES: CCCCCC1=NC=CC(C)=C1
Chemistry, Properties & Perfumer Guide
The Chemistry
4-Methyl-2-pentylpyridine belongs to the alkylpyridine class, synthetic molecules characterized by a nitrogen-containing aromatic ring. While pyridine derivatives occur naturally in some foods and tobacco smoke, this specific compound is exclusively synthetic. It’s typically produced through condensation reactions between pentanal and methylamine derivatives, followed by cyclization. The pentyl side chain contributes to its lipophilic character and persistence in fragrance compositions.
Physical & Chemical Properties
| Appearance | Colorless to pale yellow liquid |
|---|---|
| Odor Threshold | Extremely low (parts per billion) |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.1-0.5% | Up to 1% | Used sparingly for dramatic effect |
| Functional Fragrance | 0.01-0.1% | Up to 0.3% | Masking agent for industrial products |
Classic Accords
Tip: Always pre-dilute to 10% in alcohol before blending – the raw material can overwhelm other notes.
Alternatives & Comparisons
Offers similar pyridine character but with popcorn-like nuances, useful when less aggression is desired.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
Not currently restricted by IFRA standards.
GHS Classification
RIFM Assessment
Limited safety data available – recommended maximum 0.5% in leave-on products.
Sustainability
As a synthetic material, 4-Methyl-2-pentylpyridine has minimal environmental impact in production. Its extreme potency means very small quantities are needed, reducing overall chemical load in formulations compared to less powerful alternatives.
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References
- Burdock, G.A. (2010). Fenaroli’s Handbook of Flavor Ingredients. CRC Press.
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorIngredient Data Sheet
CAS 84625-54-7Physical Properties
| Molecular Weight | 163.26 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 3.5🔬 PubChem |
| Boiling Point | 217 °C🔬 EPA CompTox |
| Vapor Pressure | 0.0617 mmHg @ 25°C📊 OPERA |
| Flash Point | 90.6 °C🔬 EPA CompTox |
| Involatility Index | 0.0052💻 Calculated |
| log Kp (skin permeability) | -1.211💻 Calculated |
| SMILES | CCCCCC1=NC=CC(=C1)C🔬 PubChem |
Volatility & Performance
| Fragrance Note | Heart💻 Calculated |
| Volatility Class | Very slow💻 Calculated |
| Persistence Score | 2.3 / 5💻 Calculated |
Odor & Flavor
| Primary Descriptors | muskywoody• leffingwell |
| Functional Groups | aromatic💻 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: DTXSID90233628
Physical Properties
| Molecular Weight | 163.264 g/mol🔬 EPA CompTox |
| Density | 0.909 g/cm^3📊 OPERA |
| Boiling Point | 231.237 °C📊 OPERA |
| Melting Point | 31.393 °C📊 OPERA |
| Flash Point | 95.189 °C📊 OPERA |
| Refractive Index | 1.492 Dimensionless📊 OPERA |
| Molar Volume | 181.27 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 3.675 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 1.628 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 3.112 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5.72 Log10 unitless📊 OPERA |
| Water Solubility | 0.014 mol/L📊 OPERA |
| Henry's Law Constant | 0.001 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.048 mmHg📊 OPERA |
| Viscosity | 2.814 cP📊 OPERA |
| Surface Tension | 32.073 dyn/cm📊 OPERA |
| Thermal Conductivity | 126.8 mW/(m*K)📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 12.89 Ų💻 Computed |
| H-Bond Donors | 0 count💻 Computed |
| H-Bond Acceptors | 1 count💻 Computed |
| Rotatable Bonds | 4 count💻 Computed |
| Aromatic Rings | 1 count💻 Computed |
| Molar Refractivity | 52.617 cm^3/mol📊 OPERA |
| Polarizability | 20.859 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.
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