In short
Aldehyde C-11 undecylic, undecanal, is a saturated aliphatic aldehyde with a soapy, waxy, floral-citrus smell. It is one of the classic aldehydes used for sparkle in aldehydic florals.
What Aldehyde C-11 Undecylic (Undecanal) smells like
Undecanal (aldehyde C-11 undecylic) is a waxy, soapy aldehyde with a floral, citrus-leaning character. dsm-firmenich describes it as classic aldehydic with waxy and floral notes; Kao as pleasant, waxy or floral; other suppliers list waxy, soapy, aldehydic, citrus, green and fatty. It is softer and more floral than decanal, and less green and rosy than its unsaturated sibling, the undecylenic aldehyde.
- Leading note
- Waxy, soapy aldehydic
- Clear facets
- Floral
- Supporting facets
- Citrus
- Faint facets
- Green
- Character
- Waxy, soapy, clean, soft
What makes Aldehyde C-11 Undecylic (Undecanal) distinctive
It is the clean, soapy-waxy C-11. Where the undecylenic aldehyde is greener, rosier and slightly metallic, undecylic is smoother and soapier, closer to clean skin and laundry than to citrus.
How Aldehyde C-11 Undecylic (Undecanal) is used
Used for aldehydic, clean-floral effects in classic aldehydic florals and in soap and laundry fragrance.
Typical role: modifier (used in small amounts to change the character of a blend); lift (adds diffusion and radiance, especially at the top).
How Aldehyde C-11 Undecylic (Undecanal) differs from similar materials
- Aldehyde C-10 (Decanal)
- Decanal is the more powerful, more specifically orange-peel aldehyde; undecanal is softer, soapier and more floral.
- Aldehyde C-11 Undecylenic (10-Undecenal)
- Fraterworks describes the undecylenic aldehyde as greener and more floral-rose than undecylic; undecylic is the waxier, soapier one. (compared directly by a cited source)
- Aldehyde C-12 Lauric (Dodecanal)
- Dodecanal is waxier and creamier, with a violet note in high dilution; undecanal is cleaner and more floral-soapy.
An asterisk marks a difference that a cited source states directly. The others compare the published descriptions of each material. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.
Formulation considerations
Strong and oxidisable; dose from dilution. Not to be confused with aldehyde C-11 undecylenic, a different, greener material.
Identity and classification
- Type
- Aroma chemical
- Origin
- Occurs in nature
- Odour family
- Aldehydic / Floral
- Note position
- Top note
- Physical form at room temperature
- Liquid
- Also known as
- Undecanal
- CAS number
- 112-44-7
- Molecular formula
- C11H22O
- Molecular weight
- 170.29 g/mol
- IUPAC name
- undecanal
The CAS number, formula and molecular weight are taken from PubChem compound 8186, whose own record lists this CAS number; checked 19 October 2026.
Safety and compliance
Hazard classification of the neat substance, as PubChem summarises it, read 26 October 2026. Companies notifying the ECHA C&L Inventory classify it (1,877 reports): H315 causes skin irritation (84% of reports); H412 harmful to aquatic life with long lasting effects (15.8% of reports). Unless it is harmonised, this is the notifiers' own classification, not a binding one.
This page is general information, not a safety assessment or a specification. Confirm identity, composition, IFRA status and allergen content from your supplier's documents for the lot you hold.
Materials it works with
-
Aldehyde C-11 Undecylenic (10-Undecenal)
Aroma chemical · Aldehydic / Floral — aldehydic, waxy, clean, ozonic
-
Aldehyde C-12 Lauric (Dodecanal)
Aroma chemical · Aldehydic / Floral — aldehydic, waxy, soapy, violet
-
Aldehyde C-12 MNA
Aroma chemical · Aldehydic / Woody — aldehydic, resinous, ambergris, incense
-
Aldehyde C-10 (Decanal)
Aroma chemical · Aldehydic / Citrus — aldehydic, waxy, orange peel, fatty
Used in formulas and accords
Used in 5 published formulas
Aldehyde C-11 Undecylic (Undecanal) is an ingredient in 5 perfume formulas in the Formula & Accord Library.
RUŌOD House Originals
Original compositions by RUŌOD House.
Further reading
Questions about Aldehyde C-11 Undecylic (Undecanal)
Is Aldehyde C-11 Undecylic (Undecanal) natural or synthetic?
The molecule occurs in nature. Commercial Aldehyde C-11 Undecylic (Undecanal) may be made by synthesis or obtained from natural sources, so check the supplier's specification if the distinction matters to you.
What is the CAS number of Aldehyde C-11 Undecylic (Undecanal)?
112-44-7. It was checked against PubChem on 19 October 2026.
Which published formulas use Aldehyde C-11 Undecylic (Undecanal)?
Aldehyde C-11 Undecylic (Undecanal) is used in 5 published formulas in the RUŌOD Lab Formula & Accord Library, including Birch Ghost, Pine Tar Sauna and Steam Razor. Each is listed with a link under "Used in formulas and accords" on this page.
Sources
- PubChem — compound 8186, checked 19 October 2026.
- PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
- dsm-firmenich — Aldehyde C-11 Undecylic, via SpecialChem — manufacturer's description.
- Kao Chemicals — Aldehyde C-11 Undecyl — manufacturer's description.
- Fraterworks — Aldehyde C-11 undecylic — distributor's description.
- ChemicalBook — undecanal (CAS 112-44-7) — odour database.
- Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 20 October 2026. Evidence: several independent published descriptions, which agree. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.