Undecanoic acid (C11H22O2): structure, properties and hazards

Names and identifiers

IUPAC name: undecanoic acid
Synonyms: undecylic acid, C11:0, Hendecanoic acid
+ 36 more
Undecylic acid, n-Undecoic acid, n-Undecanoic acid, n-Undecylic acid, Undecoic acid, 1-Decanecarboxylic acid, DTXSID8021690, NSC-7885, 138ON3IIQG, CHEBI:32368, DTXCID001690, RefChem:193083, 203-964-2, undecanoate, FEMA No. 3245, Undecanoate [USAN], MFCD00002730, Undekansaeure, Undecanoate;Hendecanoic acid, NSC7885, FA 11:0, undecanoicacid, 1-decanecarboxylate, NSC 7885, EINECS 203-964-2, UNII-138ON3IIQG, BRN 1759287, AI3-02280, undecansäure, Undecanoic acid, 98%, bmse000563, Hendecanoic acid; C11:0, Undecanoic acid (Standard), SCHEMBL9266, NCIOpen2_009435, 4-02-00-01068 (Beilstein Handbook Reference)
Molecular formula: C₁₁H₂₂O₂
Empirical formula: C₁₁H₂₂O₂
Molecular weight: 186.29 g/mol
Exact mass: 186.16198
CAS number: 112-37-8
PubChem CID: 8180
Canonical SMILES: CCCCCCCCCCC(=O)O
Isomeric SMILES: CCCCCCCCCCC(=O)O
InChI: InChI=1S/C11H22O2/c1-2-3-4-5-6-7-8-9-10-11(12)13/h2-10H2,1H3,(H,12,13)
InChIKey: ZDPHROOEEOARMN-UHFFFAOYSA-N
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Physical properties

TemperaturePressureDensity

Appearance: Undecanoic acid is a white crystalline solid. Insoluble in water. Specific gravity 0.85. Hence floats on water.[1]
2 values
From CAMEO Chemicals, the most authoritative source here.
Value As written Source
–shown Undecanoic acid is a white crystalline solid. Insoluble in water. Specific gravity 0.85. Hence floats on water. [1] CAMEO Chemicals
– Other Solid [2] EPA Chemical Data Reporting (CDR)
Melting point: 28.5 °C (83.3 °F, USCG 1999)[1]
Boiling point: 227.9 °C (442.2 °F) at 160 mmHg (USCG, 1999)[1]
Density: 0.891 (USCG, 1999) - Less dense than water[1]
Flash point: greater than 110 °C (230 °F, USCG 1999)[1]

Value	As written	Source
–shown	Undecanoic acid is a white crystalline solid. Insoluble in water. Specific gravity 0.85. Hence floats on water.	[1] CAMEO Chemicals
–	Other Solid	[2] EPA Chemical Data Reporting (CDR)

Each value as its source reports it, with the source's number after it (listed under References). Where several sources report a property, the row shows the value most of them agree on, the rule the app uses; open the values to see every one.

Calculated

Heavy atoms: 13
Rings: 0
Aromatic rings: 0
Fraction sp³ carbons (Fsp3): 0.91
H-bond donors: 1
H-bond acceptors: 1 computed here · PubChem 2
Rotatable bonds: 9
TPSA (Å²): 37.3
Formal charge: 0
XLogP3: 3.7 PubChem
Complexity: 121 PubChem
Stereocenters: None
Double-bond geometry: None specified
Point group: C1 of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

C70.92%
H11.90%
O17.18%

Isotope pattern

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P: 3.6 Crippen (Wildman and Crippen 1999)
log S (water solubility): -2.67 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 1.56 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 186.29
log P ≤ 5 (Crippen): 3.6
H-bond donors ≤ 5: 1
H-bond acceptors ≤ 10: 1

Passes all four rules.

¹³C NMR shifts, predicted

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

Warning

Most widely reported: 167 company reports to ECHA. Source [3].

Harmful or irritant

H315Causes skin irritation (98.8% of reports)
H319Causes serious eye irritation (84.4% of reports)
H335May cause respiratory irritation (82.6% of reports)

Precautionary statements: P261, P264, P264+P265, P271, P280, P302+P352, P304+P340, P305+P351+P338, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, P501

View all classifications (2)

[3] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 1.2% (2 of 167) of reports.
[3] European Chemicals Agency (ECHA) · 167 reports · WarningH315, H319, H335

First aid

Inhalation: Call for medical aid. Remove the victim to fresh air. If not breathing give artificial respiration. If breathing is difficult give oxygen. EYES OR skin: Flush with copious amounts of water for at least 15 minutes. Insure adequate flushing of the eyes by separating the eyelids with the fingers. (USCG, 1999)[1]

Safety data sheets on the supplier’s page: Alfa Chemistry, AstaTech, Inc., Biorbyt.

Always read the supplier’s safety data sheet before working with it.

Spectra

Experimental spectra held by these sources; each link opens the source's own record.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

[1]CAMEO Chemicals · Public domain (NOAA) · via PubChem · retrieved 2026-10-14
[2]EPA Chemical Data Reporting (CDR) · Public domain (US EPA) · via PubChem · retrieved 2026-10-14
[3]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[4]Human Metabolome Database (HMDB) · Linked only · via PubChem · retrieved 2026-10-14
[5]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
[6]MassBank of North America (MoNA) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
[7]NIST Mass Spectrometry Data Center · Linked only · via PubChem · retrieved 2026-10-14
[8]MassBank Europe · Linked only · via PubChem · retrieved 2026-10-14
·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
·Literature on PubChem

Data last updated 2026-10-14.

Similar structures

Tanimoto similarity on Morgan fingerprints (radius 2) with RDKit 2026.09, at least 45%.