The nomenclature of butanone primarily refers to its systematic IUPAC name, butanone. However, it is also widely known by common names such as methyl ethyl ketone (MEK) and ethyl methyl ketone.
Understanding Butanone's Nomenclature
Butanone is an organic compound belonging to the ketone family. Its naming conventions include both a systematic IUPAC name and common industrial aliases, reflecting its chemical structure and practical applications.
IUPAC Name: Butanone
The systematic name for this compound, as defined by the International Union of Pure and Applied Chemistry (IUPAC), is butanone. This name provides specific details about its chemical structure:
- "But-": Indicates a carbon chain composed of four carbon atoms.
- "-an-": Signifies that all carbon-carbon bonds within the chain are single bonds (saturated).
- "-one": Denotes the presence of a carbonyl functional group (C=O) located within the carbon chain, characteristic of a ketone.
For a four-carbon chain, the carbonyl group can only be positioned at the second or third carbon to qualify as a ketone. When numbered from either end, this position becomes the 2-position (e.g., butan-2-one). Due to the inherent uniqueness of this position in a butanone structure, the "2-" is often omitted, making "butanone" the complete and unambiguous IUPAC name.
Common Names and Aliases
In addition to its IUPAC designation, butanone is frequently referred to by several common names, especially in industrial and commercial contexts where it is produced on a large scale:
- Methyl Ethyl Ketone (MEK): This is arguably the most prevalent common name. It clearly indicates the two alkyl groups—a methyl group (CH₃) and an ethyl group (CH₂CH₃)—attached to the central carbonyl carbon.
- Ethyl Methyl Ketone: This name is an alternative phrasing of "methyl ethyl ketone" and is functionally interchangeable.
Chemical Identity and Structure
Butanone's chemical structure is represented by the formula CH₃C(O)CH₂CH₃. This formula explicitly shows the four-carbon backbone and the internal carbonyl group (C=O), which defines it as a ketone. It is known as a colorless liquid that possesses a sharp, sweet odor, often compared to that of acetone.
Summary of Butanone Nomenclature
To summarize the various ways butanone is named:
| Type of Name | Name | Description |
|---|---|---|
| IUPAC Name | Butanone | The systematic name based on chemical structure rules. |
| Common Name | Methyl Ethyl Ketone (MEK) | A widely used industrial and commercial name based on alkyl groups. |
| Common Name | Ethyl Methyl Ketone | An alternative common name for the compound. |
| Chemical Formula | CH₃C(O)CH₂CH₃ | Represents the arrangement of atoms in the molecule. |
