6-Methylquinoline (CAS 91-62-3) — Balsamic Base Note Fragrance Ingredient
6-Methylquinoline
CAS 91-62-3
What Is 6-Methylquinoline?
6-Methylquinoline is a synthetic aromatic compound primarily used in niche perfumery. It’s encountered in sophisticated fragrances seeking a leathery or tobacco-like character. This ingredient matters because it adds complexity and depth to masculine and unisex scents, often recreating the nostalgic smell of old books or fine leather goods.
Safety Profile
USE WITH AWARENESSWhat Does 6-Methylquinoline Smell Like?
6-Methylquinoline delivers an intensely aromatic, leathery-tobacco character with bitter quinoline undertones. Initially sharp and medicinal, it evolves into a warm, animalic base reminiscent of aged leather-bound books. The dry-down reveals subtle smoky nuances with a persistent woody-ambery trail. Its complex profile bridges the gap between synthetic precision and natural warmth.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Used to recreate the distinctive birch tar leather accord, providing a smoky, tarry backbone that defines this classic.
Contributes to the legendary leather accord, blending with birch tar and florals for a rugged yet refined masculine character.
2D Molecular Structure
SMILES: CC1=CC2=CC=CN=C2C=C1
Chemistry, Properties & Perfumer Guide
The Chemistry
6-Methylquinoline belongs to the quinoline class of heterocyclic aromatic compounds. It’s synthesized through Skraup or Doebner-Miller reactions, where aniline derivatives undergo cyclization with glycerol or acrolein equivalents. The methyl group at position 6 influences both volatility and odor characteristics. Unlike natural quinoline derivatives found in coal tar, this synthetic version offers purity control.
Physical & Chemical Properties
| Boiling Point | Not available |
|---|---|
| Density | Not available |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.1-0.5% | Up to 1% | Used sparingly for leather/tobacco effects |
Classic Accords
Tip: Always pre-dilute to 1% in ethanol before blending due to intense odor impact.
Alternatives & Comparisons
Offers similar leathery character but with more pronounced green-earthy facets, useful when needing additional freshness.
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 for professional use only.
Sustainability
As a synthetic material, 6-methylquinoline production avoids natural resource depletion. However, its synthesis typically involves petrochemical feedstocks. Modern production methods aim to reduce environmental impact through catalytic processes and solvent recovery systems.
Explore 6-Methylquinoline
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References
- Bauer et al. (2001). Common Fragrance and Flavor Materials. Wiley-VCH.
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorIngredient Data Sheet
CAS 91-62-3Physical Properties
| Molecular Weight | 143.18 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 2.6🔬 PubChem |
| Boiling Point | 258.6 °C🔬 EPA CompTox |
| Vapor Pressure | 3 mmHg @ 25°C📊 OPERA |
| Flash Point | 112.8 °C🔬 EPA CompTox |
| Involatility Index | 0.2702💻 Calculated |
| log Kp (skin permeability) | -1.727💻 Calculated |
| SMILES | CC1=CC2=C(C=C1)N=CC=C2🔬 PubChem |
Volatility & Performance
| Fragrance Note | Heart💻 Calculated |
| Volatility Class | Moderate💻 Calculated |
| Persistence Score | 0.5 / 5💻 Calculated |
Odor & Flavor
| Primary Descriptors | animalicfloralsweettobaccowoody• leffingwell |
| Functional Groups | aromatic💻 RDKit |
| “Powerful and penetrating, heavy nauseating odor in high concentration, but sweet, floral-tobacco-like with a discrete Civet-like note”📖 Arctander | |
| 6-Methylquinoline has a pungent, heavy odor.📖 Fenaroli | |
Regulatory Status
| IOFI Classification | Nature Identical📖 Fenaroli |
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: DTXSID3020887
Physical Properties
| Molecular Weight | 143.189 g/mol🔬 EPA CompTox |
| Density | 1.063 g/cm^3🔬 EPA CTX |
| Boiling Point | 259.053 °C🔬 EPA CTX |
| Melting Point | -22.028 °C🔬 EPA CTX |
| Flash Point | 109.05 °C🔬 EPA CTX |
| Refractive Index | 1.625 Dimensionless📊 OPERA |
| Molar Volume | 133.048 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 2.57 Log10 unitless🔬 EPA CTX |
| LogD (pH 5.5) | 2.436 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 2.568 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5.74 Log10 unitless📊 OPERA |
| Water Solubility | 0.013 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 1.503 mmHg🔬 EPA CTX |
| Viscosity | 4.621 cP📊 OPERA |
| Surface Tension | 41.653 dyn/cm📊 OPERA |
| Thermal Conductivity | 138.67 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 | 0 count💻 Computed |
| Aromatic Rings | 2 count💻 Computed |
| Molar Refractivity | 47.012 cm^3/mol📊 OPERA |
| Polarizability | 18.637 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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