(4E)-2-Oxohexenoic acid, often referred to as 2-oxohex-4-enoic acid, is an organic compound classified as a 2-oxo monocarboxylic acid. It possesses the chemical formula C6H8O3 and is characterized by a keto group at the second carbon position and a carbon-carbon double bond at the fourth carbon, specifically in the trans (E) configuration. This molecule is functionally related to a hex-4-enoic acid and acts as the conjugate acid of a 2-oxohex-4-enoate.
Understanding (4E)-2-Oxohexenoic Acid
The name (4E)-2-Oxohexenoic acid provides crucial information about its chemical structure:
- Hexenoic Acid: Indicates a six-carbon chain with a carboxylic acid group (-COOH) at one end and one carbon-carbon double bond. The "en" signifies the presence of the double bond, differentiating it from a saturated "hexanoic" acid.
- -4-: Specifies that the double bond is located between the fourth and fifth carbon atoms in the chain, starting from the carboxylic acid carbon as C1.
- (4E)-: Denotes the stereochemistry of the double bond. 'E' (from German entgegen, meaning "opposite") signifies a trans configuration, where the higher-priority groups on each carbon of the double bond are on opposite sides.
- 2-Oxo-: Indicates the presence of a carbonyl group (C=O, a keto group) at the second carbon atom, adjacent to the carboxylic acid group. This makes it an alpha-keto acid.
Key Characteristics
This compound is a type of unsaturated alpha-keto acid. Alpha-keto acids are significant in biochemistry, often participating in metabolic pathways.
Here's a summary of its key chemical properties:
| Property | Description |
|---|---|
| IUPAC Name | (4E)-2-Oxohexenoic acid |
| Synonym | 2-Oxohex-4-enoic acid |
| Chemical Formula | C6H8O3 |
| Classification | 2-oxo monocarboxylic acid |
| Functional Group | Carboxylic acid, ketone, alkene (trans) |
| Related Compounds | Functionally related to hex-4-enoic acid; it is the conjugate acid of a 2-oxohex-4-enoate, meaning it can donate a proton to form its corresponding base. |
| PubChem CID | 5280996 |
Structural Insights
The presence of the 2-oxo group next to the carboxylic acid group (alpha position) means it can undergo various reactions typical of alpha-keto acids, such as oxidative decarboxylation. The double bond at position 4, with its specific (E) configuration, introduces rigidity and specific spatial arrangement to the molecule. This geometric isomerism can impact its biological activity or physical properties.
Biological Relevance
While specific biological roles for (4E)-2-Oxohexenoic acid are not widely detailed, alpha-keto acids, in general, are crucial intermediates in various metabolic cycles. They are often involved in:
- Amino acid metabolism: Acting as precursors or breakdown products of amino acids.
- Energy production: Feeding into the Krebs cycle.
- Biosynthesis: Serving as building blocks for other organic molecules.
Its unsaturated nature might also play a role in lipid metabolism or as a signaling molecule, similar to other unsaturated fatty acids or their derivatives.
