2-Phenylpropionaldehyde dimethyl acetal (CAS 90-87-9) — Floral Middle-top Note Fragrance Ingredient
2-Phenylpropionaldehyde dimethyl acetal
CAS 90-87-9
What Is 2-Phenylpropionaldehyde dimethyl acetal?
2-Phenylpropionaldehyde dimethyl acetal is a synthetic fragrance ingredient used in perfumes and scented products. It contributes a fresh, floral-green character with fruity undertones. This molecule matters because it helps create long-lasting, complex floral accords while being more stable than some natural alternatives.
Safety Profile
GENERALLY SAFEWhat Does 2-Phenylpropionaldehyde dimethyl acetal Smell Like?
2-Phenylpropionaldehyde dimethyl acetal opens with a crisp green apple peel sharpness that quickly softens into a dewy floral heart reminiscent of lily-of-the-valley with a hint of pear skin. The dry-down reveals a subtle powdery-musky undertone that lingers close to the skin. Unlike its aldehyde precursor, the acetal form provides a more rounded, less aggressive scent profile with better stability in formulations.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Used as a modern floralizer that bridges the citrus top notes to the jasmine heart, providing airy freshness without overpowering the delicate composition.
Contributes to the crisp apple-watery floral accord that defines this summer fragrance, enhancing diffusion while maintaining transparency.
2D Molecular Structure
SMILES: COC(OC)C(C)C1=CC=CC=C1
Chemistry, Properties & Perfumer Guide
The Chemistry
2-Phenylpropionaldehyde dimethyl acetal belongs to the acetal class of fragrance compounds, formed by protecting the reactive aldehyde group of hydratropic aldehyde with methanol. This modification increases stability against oxidation while maintaining desirable olfactory properties. Industrially produced via acid-catalyzed acetalization, the compound exhibits chirality at the benzylic carbon, though most commercial material is racemic.
Physical & Chemical Properties
| Appearance | Colorless to pale yellow liquid |
|---|---|
| Boiling Point | 210-215 °C (estimated) |
| Density | ~1.0 g/cm³ (estimated) |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.5-2% | Up to 5% | Floral-fruity modifier |
| Functional Fragrance | 0.1-0.5% | Up to 1% | Freshness booster |
Classic Accords
Tip: Use in citrus-floral compositions to bridge top and middle notes while improving shelf stability.
Alternatives & Comparisons
More intense floral character with better tenacity for richer compositions.
For brighter but less stable green-floral effects when oxidation isn’t a concern.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
Not currently restricted by IFRA standards.
RIFM Assessment
Under review by RIFM as of 2023.
Sustainability
As a synthetic material, production avoids agricultural land use. Current manufacturing routes show good atom economy with methanol recovery systems in place. Potential exists for bio-based phenyl precursors to further improve sustainability profile.
Explore 2-Phenylpropionaldehyde dimethyl 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 errorIngredient Data Sheet
CAS 90-87-9Physical Properties
| Molecular Weight | 180.24 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 2.4🔬 PubChem |
| Boiling Point | 111 °C🔬 EPA CompTox |
| log Kp (skin permeability) | -2.095💻 Calculated |
| SMILES | CC(C1=CC=CC=C1)C(OC)OC🔬 PubChem |
Volatility & Performance
| Fragrance Note | Top💻 Calculated |
Odor & Flavor
| Primary Descriptors | citrusfloralgreenmushroom• leffingwell |
| Functional Groups | etheraromatic💻 RDKit |
| “Powerful, earthy, warm-spicy and green, deep-fruity odor, reminiscent of Walnut, Mushroom (Champignon) with a slightly floral-fruity undertone.”📖 Arctander | |
| 2-Phenylpropionaldehyde dimethyl acetal has a strong, warm, spicy odor reminiscent of walnut with a warm, mushroom, nut-like taste.📖 Fenaroli | |
Flavor Notes (Arctander)
| “Warm-earthly, distinctly mushroomy taste in dilutions below 5 ppm. Higher concentrations are mostly nut-like, spicy or sharp. The Acetal is also used in many types of flavor composition: Berry complexes, floral bases, Rose flavor, fruit complexes, imitation Honey, Nut and Spice, and particularly in ”📖 Arctander |
Regulatory Status
| FEMA Number | FEMA 2888⚖️ FEMA GRAS |
| GRAS Status | Generally Recognized as Safe⚖️ FEMA GRAS |
| IOFI Classification | Artificial📖 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: DTXSID6047109
Physical Properties
| Molecular Weight | 180.247 g/mol🔬 EPA CompTox |
| Density | 0.992 g/cm^3🔬 EPA CTX |
| Boiling Point | 231.658 °C📊 OPERA |
| Melting Point | 16.371 °C📊 OPERA |
| Flash Point | 86.314 °C📊 OPERA |
| Refractive Index | 1.485 Dimensionless📊 OPERA |
| Molar Volume | 185.621 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 2.579 Log10 unitless🔬 EPA CTX |
| LogD (pH 5.5) | 2.596 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 2.596 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5.71 Log10 unitless📊 OPERA |
| Water Solubility | 0.008 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.051 mmHg📊 OPERA |
| Viscosity | 3.55 cP📊 OPERA |
| Surface Tension | 31.824 dyn/cm📊 OPERA |
| Thermal Conductivity | 128.378 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 | 4 count💻 Computed |
| Aromatic Rings | 1 count💻 Computed |
| Molar Refractivity | 53.153 cm^3/mol📊 OPERA |
| Polarizability | 21.071 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.
