August 24, 2025 | UR Gate
Linoleic Acid (C18H32O2) Structure, Properties and Nomenclature
Discover Linoleic Acid (C18H32O2), an essential omega-6 fatty acid. Learn its structure, key properties, IUPAC name, synonyms, and its vital roles in skin health, inflammation, and as a precursor to other fatty acids.
What is Linoleic Acid (C18H32O2)?
Linoleic acid is an essential omega-6 polyunsaturated fatty acid, meaning the human body cannot synthesize it and must obtain it from the diet. It is characterized by an 18-carbon chain with two double bonds located at the cis configuration, specifically at the ninth and twelfth carbon atoms from the methyl end. Linoleic acid is a vital component of cell membranes and plays a crucial role in maintaining skin barrier function, regulating inflammation, and serving as a precursor for other important fatty acids, including arachidonic acid. It is commonly found in vegetable oils such as soybean oil, corn oil, sunflower oil, and safflower oil.
Properties of Linoleic Acid (C18H32O2)
| Property | Value |
|---|---|
| Molecular Formula | C₁₈H₃₂O₂ |
| Molecular Weight | 280.45 g/mol |
| Density | Approximately 0.902 g/mL (at 20°C for liquid) |
| Boiling Point | 229–230 °C at 15 mmHg (decomposes at atmospheric pressure) |
| Melting Point | -5 °C |
| Hybridization | Carbons involved in double bonds are sp² hybridized; all other carbon atoms are sp³ hybridized. The carboxyl group carbon is sp² hybridized. |
| Appearance | Colorless to yellowish oily liquid |
| Solubility | Insoluble in water; soluble in most organic solvents like ethanol, ether, and chloroform. |
Nomenclature of Linoleic Acid
- Common name: Linoleic acid
- IUPAC name: (9Z,12Z)-octadeca-9,12-dienoic acid
Synonyms
- cis,cis-9,12-Octadecadienoic acid
- (9Z,12Z)-Octadecadienoic acid
- (9Z,12Z)-Δ⁹,¹²-Octadecadienoic acid
- LA
- Oleopalmitic acid (obsolete)
