Acetyl group
| Names | |
|---|---|
| IUPAC name Acetyl (preferred to ethanoyl) | |
| Systematic IUPAC name Methyloxidocarbon(•) (additive) | |
| Identifiers | |
| 3D model (JSmol) | |
| Abbreviations | Ac | 
| 1697938 | |
| ChEBI | |
| ChemSpider | |
| 786 | |
| PubChem CID | |
| 
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| 
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| Properties | |
| C2H3O | |
| Molar mass | 43.045 g·mol−1 | 
| Thermochemistry | |
| Std enthalpy of formation (ΔfH⦵298) | −15 to −9 kJ mol−1 | 
| Related compounds | |
| Related compounds | Acetone Carbon monoxide Acetic acid | 
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references | |
In organic chemistry, an acetyl group is a functional group denoted by the chemical formula −COCH3 and the structure −C(=O)−CH3. It is sometimes represented by the symbol Ac (not to be confused with the element actinium). In IUPAC nomenclature, an acetyl group is called an ethanoyl group.
An acetyl group contains a methyl group (−CH3) that is single-bonded to a carbonyl (C=O), making it an acyl group. The carbonyl center of an acyl radical has one non-bonded electron with which it forms a chemical bond to the remainder (denoted with the letter R) of the molecule.
The acetyl moiety is a component of many organic compounds, including acetic acid, the neurotransmitter acetylcholine, acetyl-CoA, acetylcysteine, acetaminophen (also known as paracetamol), and acetylsalicylic acid (also known as aspirin).