3,7-Dimethyloctanenitrile (CAS 40188-41-8) — Citrus Top to middle Note Fragrance Ingredient

Citrus · Woody

3,7-Dimethyloctanenitrile

CAS 40188-41-8

Origin
synthetic
Note
Top to middle
IFRA
Generally safe
Data as of: Apr 2026

What Is 3,7-Dimethyloctanenitrile?

3,7-Dimethyloctanenitrile is a synthetic fragrance ingredient used to add fresh, citrusy notes to perfumes and scented products. You’ll encounter it in modern citrus colognes, fabric softeners, and household cleaners. This nitrile compound matters because it provides long-lasting citrus character without the volatility of natural citrus oils, making fragrances more durable while maintaining a natural-smelling profile.

Safety Profile

GENERALLY SAFE
Generally safeUse with awarenessProfessional use
IFRA compliant
No known phototoxicity
CAS
40188-41-8
Formula
Mixture
MW
Variable
Odor Family
Citrus · Woody
Layer 1 · Enthusiast

What Does 3,7-Dimethyloctanenitrile Smell Like?

Opens with a burst of crisp, aldehydic citrus reminiscent of freshly peeled mandarin with a green stem still attached. The heart reveals a clean laundry muskiness that prevents excessive sweetness, while the dry-down develops into a woody-ambergris base note with surprising tenacity for a citrus material. Unlike natural citrus oils, it maintains its character for hours rather than minutes, evolving from juicy to polished.

Scent Profile

In Famous Fragrances

Fragrance associations may not reflect actual formulations.

Light Blue(Dolce & Gabbana, 2001)

Used as the synthetic citrus backbone that persists throughout the wear, complementing the natural bergamot top notes while providing durability the natural oils lack.

CK One(Calvin Klein, 1994)

Provides the unisex citrus freshness that blends seamlessly with green tea and musk notes, chosen for its ability to smell clean without soapiness.

Layer 2

2D Molecular Structure

3,7-Dimethyloctanenitrile

SMILES: CC(C)CCCC(C)CC#N

Chemistry, Properties & Perfumer Guide

The Chemistry

3,7-Dimethyloctanenitrile belongs to the nitrile class of fragrance compounds, characterized by a -C≡N functional group attached to a branched hydrocarbon chain. While nitriles occur rarely in nature, this synthetic material mimics the behavior of citrus terpenes with greater stability. Industrial synthesis typically involves hydrocyanation of the corresponding alkene precursor followed by purification to remove residual cyanide compounds. The branched structure prevents polymerization and contributes to its excellent shelf stability compared to linear nitriles.

Physical & Chemical Properties

AppearanceColorless to pale yellow liquid
Boiling Point~220 °C (estimated)
Density~0.85 g/cm³ (estimated)

Perfumer Guide

Note Position
Top to middle
Volatility
Medium (2-4 hours)
Blending
Good
ApplicationTypical %RangeNotes
Fine Fragrance1-3%Up to 5%Citrus accord enhancer
Functional Products0.5-1%Up to 2%Long-lasting freshness

Classic Accords

Tip: Use with ionones to create a seamless citrus-floral transition that lasts through the heart phase.

Alternatives & Comparisons

1
Citronellyl nitrile CAS 51566-62-2

More floral-lemon character with similar stability, preferred when a rosier citrus profile is desired.

Layer 3

Safety, Regulatory & Sustainability

⚠ Regulatory Disclaimer

General reference only. Consult current IFRA Standards Library before formulating.

IFRA Status

No restrictions under IFRA 51st Amendment.

RIFM Assessment

Evaluated by RIFM in 2018 with no adverse effects noted at standard usage levels.

Sustainability

As a synthetic material, production avoids agricultural land use but requires petroleum-derived feedstocks. Recent advances allow production via bio-based isoprene, reducing carbon footprint. The nitrile group’s stability reduces environmental persistence compared to some ester alternatives.

Explore 3,7-Dimethyloctanenitrile

Browse essential oils and aroma compounds.

Browse on iHerb →

Affiliate disclosure: we may earn a small commission at no extra cost to you.

References

  1. Bauer et al. (2001). Nitriles in Modern Perfumery. Perfumer & Flavorist. Industry reference

Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.

Report a data error

Ingredient Data Sheet

CAS 40188-41-8

Physical Properties

Molecular Weight153.26 g/mol🔬 PubChem
LogP (Octanol-Water)3.7🔬 PubChem
Boiling Point221 °C🔬 EPA CompTox
Vapor Pressure0.4898 mmHg @ 25°C📊 OPERA
Flash Point77.5 °C🔬 EPA CompTox
Involatility Index0.0426💻 Calculated
log Kp (skin permeability)-1.008💻 Calculated
SMILESCC(C)CCCC(C)CC#N🔬 PubChem

Volatility & Performance

Fragrance NoteHeart💻 Calculated
Volatility ClassSlow💻 Calculated
Persistence Score0.6 / 5💻 Calculated

Odor & Flavor

Primary Descriptorscitruswoody• leffingwell
Data Sources & Attribution
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: DTXSID7052076

Physical Properties

Molecular Weight 153.269 g/mol🔬 EPA CompTox
Density 0.825 g/cm^3📊 OPERA
Boiling Point 220.68 °C📊 OPERA
Melting Point -22.106 °C📊 OPERA
Flash Point 81.54 °C📊 OPERA
Refractive Index 1.427 Dimensionless📊 OPERA
Molar Volume 187.739 cm^3/mol📊 OPERA

Partition & Solubility

LogP (Octanol-Water) 3.469 Log10 unitless📊 OPERA
LogD (pH 5.5) 3.469 Log10 unitless📊 OPERA
LogD (pH 7.4) 3.469 Log10 unitless📊 OPERA
LogKoa (Octanol-Air) 4.86 Log10 unitless📊 OPERA
Water Solubility 0 mol/L🔬 EPA CTX
Henry's Law Constant 0 atm-m3/mole📊 OPERA

Transport Properties

Vapor Pressure 0.23 mmHg📊 OPERA
Viscosity 1.586 cP📊 OPERA
Surface Tension 27.939 dyn/cm📊 OPERA
Thermal Conductivity 139.969 mW/(m*K)📊 OPERA

Molecular Descriptors

Topological Polar Surface Area 23.79 Ų💻 Computed
H-Bond Donors 0 count💻 Computed
H-Bond Acceptors 1 count💻 Computed
Rotatable Bonds 5 count💻 Computed
Aromatic Rings 0 count💻 Computed
Molar Refractivity 48.208 cm^3/mol📊 OPERA
Polarizability 19.111 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.

Similar Posts