Phenylacetaldehyde ethylene glycol acetal (CAS 101-49-5) — Floral Top to middle Note Fragrance Ingredient
Phenylacetaldehyde ethylene glycol acetal
CAS 101-49-5
What Is Phenylacetaldehyde ethylene glycol acetal?
Phenylacetaldehyde ethylene glycol acetal is a synthetic fragrance ingredient commonly found in floral perfumes and household products. It adds a fresh, green floral character reminiscent of hyacinth and lily. This versatile molecule helps create natural-smelling floral bouquets while improving stability compared to its parent aldehyde.
Safety Profile
GENERALLY SAFEWhat Does Phenylacetaldehyde ethylene glycol acetal Smell Like?
Opens with a crisp green floral burst like crushed hyacinth petals with dewy freshness. The heart reveals a honeyed floralcy with subtle rosy undertones. As it dries down, maintains a clean floral character with mild powdery facets. More stable and less pungent than phenylacetaldehyde, with better blending properties while retaining the core floral-green aroma.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Used to recreate the lily-of-the-valley accord with enhanced stability. Provides the green floral top notes that define this classic.
Contributes to the sparkling floral bouquet, particularly enhancing the carnation and rose aspects with its green floral character.
2D Molecular Structure
SMILES: C(C1OCCO1)C1=CC=CC=C1
Chemistry, Properties & Perfumer Guide
The Chemistry
Phenylacetaldehyde ethylene glycol acetal is a cyclic acetal formed by reacting phenylacetaldehyde with ethylene glycol. This chemical modification improves stability while retaining the desired floral odor characteristics. The acetal formation protects the reactive aldehyde group from oxidation and polymerization. Synthesized through acid-catalyzed condensation reactions, it offers perfumers a more stable alternative to phenylacetaldehyde.
Physical & Chemical Properties
| Appearance | Colorless to pale yellow liquid |
|---|---|
| Boiling Point | ~250 °C |
| Density | ~1.05 g/cm³ |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 1-3% | 0.5-5% | Floral compositions |
| Soap | 0.5-1% | 0.2-2% | Stable in alkaline media |
Classic Accords
Tip: Use in floral bases where phenylacetaldehyde would be too harsh or unstable.
Alternatives & Comparisons
More volatile with sharper green notes. Better for top note impact but less stable in alkaline conditions.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
No IFRA restrictions. Approved for all fragrance categories.
RIFM Assessment
RIFM safety assessment complete – no significant concerns at typical usage levels.
Sustainability
Synthesized from petrochemical feedstocks. More sustainable than natural phenylacetaldehyde extraction due to higher yield and purity. No known ecological concerns at production scale.
Explore Phenylacetaldehyde ethylene glycol acetal
Browse essential oils and aroma compounds.
Browse on iHerb →Affiliate disclosure: we may earn a small commission at no extra cost to you.
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 errorPhysicochemical Properties
DTXSID: DTXSID1059230
Physical Properties
| Molecular Weight | 164.204 g/mol🔬 EPA CompTox |
| Density | 1.092 g/cm^3📊 OPERA |
| Boiling Point | 249.023 °C📊 OPERA |
| Melting Point | 18.009 °C📊 OPERA |
| Flash Point | 107.85 °C🔬 EPA CTX |
| Refractive Index | 1.532 Dimensionless📊 OPERA |
| Molar Volume | 149.104 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 2.167 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 2.167 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 2.167 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5.86 Log10 unitless📊 OPERA |
| Water Solubility | 0.013 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.034 mmHg📊 OPERA |
| Viscosity | 4.167 cP📊 OPERA |
| Surface Tension | 39.926 dyn/cm📊 OPERA |
| Thermal Conductivity | 134.462 mW/(m*K)📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 18.46 Ų💻 Computed |
| H-Bond Donors | 0 count💻 Computed |
| H-Bond Acceptors | 2 count💻 Computed |
| Rotatable Bonds | 2 count💻 Computed |
| Aromatic Rings | 1 count💻 Computed |
| Molar Refractivity | 46.212 cm^3/mol📊 OPERA |
| Polarizability | 18.32 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.
