2-Butyrylfuran (CAS 4208-57-5) — Mid Note Fragrance Ingredient
2-Butyrylfuran
CAS 4208-57-5
What Is 2-Butyrylfuran?
2-Butyrylfuran (CAS 4208-57-5) is an aroma chemical used as a fragrance and flavour ingredient. Its odour is described as nutty, sweet and bakery, placing it within the gourmand family as a mid note with medium volatility. With a molecular weight of 138.2 (formula C8H10O2), it is handled by perfumers as a building block for compositions where a nutty character is desired. The data below is compiled from public chemical and regulatory sources.
Safety Profile
USE WITH AWARENESS
What Does 2-Butyrylfuran Smell Like?
The odour profile of 2-Butyrylfuran is reported as nutty, sweet, bakery, fruit, fish, garlic, spices, cold, sour, burnt, acid, warm, musky, sweaty, ammonia/urinous, decayed, grass, flower, chemical, edible, wood. The dominant facet is its nutty character, with the remaining notes adding nuance and complexity. As a mid note it contributes to the heart of a fragrance. Perceived intensity and exact character depend on concentration, the carrier and the surrounding accord.
Scent Profile
Profile derived from public odour-descriptor data; relative, not absolute.
Chemistry & Properties
The Chemistry
2-Butyrylfuran has the molecular formula C8H10O2 and a molecular weight of 138.2 g/mol. Its canonical SMILES representation is CCCC(=O)C1=CC=CO1. Its reported log P (XLogP) of 2.26 indicates a lipophilic, oil-soluble molecule, which informs how it partitions in a formula. Physical constants below are drawn from PubChem and EPA CompTox public datasets.
Physical & Chemical Properties
| Molecular Weight | 138.2 g/mol |
|---|---|
| Boiling Point | 203.0 °C |
| Melting Point | 32.96 °C |
| Flash Point | 77.48 °C |
| Density | 1.05 g/cm³ |
| Vapor Pressure | 0.248 mmHg |
| Water Solubility | 0.07803 g/L |
| XLogP | 2.26 |
Perfumer Guide
Alternatives & Comparisons
Ingredients occupying a similar odour space — useful as substitutes or companions when 2-Butyrylfuran is unavailable or restricted.
Shares bakery, sweet, fruit character — a candidate substitute or companion in the same odour space.
Shares bakery, sweet, fruit character — a candidate substitute or companion in the same odour space.
Shares acid, ammonia/urinous, bakery character — a candidate substitute or companion in the same odour space.
Safety & Regulatory
⚠ Regulatory Disclaimer
General reference only. IFRA, REACH and EU Cosmetics Regulation standards update periodically. Consult the current IFRA Standards Library before formulating. Not legal or regulatory advice.
IFRA Status
No IFRA restriction recorded in the data set. This is not a guarantee of unrestricted status — always confirm against the current IFRA Standards Library.
GHS Classification
Signal word: Danger
Open 2-Butyrylfuran in Fragrance Studio (Pro) for the calibrated vapour-pressure curve, the modelled odour-threshold estimate, and the substitute-matching engine across 2,900+ aromachemicals.
References & Sources
- PubChem Compound Summary (NIH) — search by InChIKey
- EPA CompTox Chemicals Dashboard — physicochemical & fate data
- IFRA Standards Library (49th / 51st Amendment)
Data: PubChem (NIH), EPA CompTox, IFRA. Last reviewed: Jun 2026.
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