| Acetophenone | |
|---|---|
|
1-phenylethanone |
|
|
Other names
Phenyl methyl ketone, ACP, Phenylethanone |
|
| Identifiers | |
| CAS number | 98-86-2 |
| PubChem | 7410 |
| ChemSpider | 7132 |
| UNII | RK493WHV10 |
| DrugBank | DB04619 |
| KEGG | C07113 |
| ChEBI | CHEBI:27632 |
| ChEMBL | CHEMBL274467 |
| Jmol-3D images | Image 1 Image 2 |
|
|
|
|
| Properties | |
| Molecular formula | C8H8O |
| Molar mass | 120.15 g mol−1 |
| Density | 1.028 g/cm³ |
| Melting point |
19–20 °C |
| Boiling point |
202 °C |
| Solubility in water | 5.5 g/L at 25 °C 12.2 g/L at 80 °C |
| Hazards | |
| MSDS | External MSDS |
| EU classification | Xn |
| NFPA 704 |
2
0
|
| Flash point | 77 °C |
| Supplementary data page | |
| Structure and properties |
n, εr, etc. |
| Thermodynamic data |
Phase behaviour Solid, liquid, gas |
| Spectral data | UV, IR, NMR, MS |
| (verify) (what is: /?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
|
| Infobox references | |
Acetophenone is the organic compound with the formula C6H5C(O)CH3. It is the simplest aromatic ketone. This colourless, viscous liquid is a precursor to useful resins and fragrances.[1]
Contents |
Acetophenone can be obtained by a variety of methods. In industry, acetophenone is recovered as a by-product of the oxidation of ethylbenzene, which mainly gives ethylbenzene hydroperoxide for use in the production of propylene oxide.[1]
Commercially significant resins are produced from treatment of acetophenone with formaldehyde and base. The resulting polymers are conventionally described with the formula [(C6H5C(O)CH]x(CH2)x}n, resulting from aldol condensation. These substances are components of coatings and inks. Modified acetophenone-formaldehyde resins are produced by the hydrogenation of the aforementioned ketone-containing resins. The resulting polyol can be further crosslinked with diisocyanates.[1] These modified resins are again found in coatings, inks, as well as adhesives.
In instructional laboratories, acetophenone is converted to styrene in a two step process that illustrates the reduction of carbonyls and the dehydration of alcohols:
A similar process is used industrially but the hydrogenation step to 1-phenylethanol is done over a copper catalyst.[1]
Acetophenone is a raw material for the synthesis of some pharmaceuticals[2] [3] and is also listed as an approved excipient by the U.S. FDA.[4] In a 1994 report released by five top cigarette companies in the U.S., acetophenone was listed as one of the 599 additives to cigarettes.[5]
Acetophenone is used to create fragrances that resemble almond, cherry, honeysuckle, jasmine, and strawberry. It is used in chewing gum.[6] Being prochiral, acetophenone is also a popular test substrate for asymmetric transfer hydrogenation experiments. Acetophenone is also commonly used as a flavouring in many cherry flavoured sweets and drinks, as it costs far less and proves as satisfying to consumers this way.
Acetophenone occurs naturally in many foods including apple, cheese, apricot, banana, beef, and cauliflower.
In the late 19th and early 20th centuries, acetophenone was used in medicine.[7] It was marketed as a hypnotic and anticonvulsant under brand name Hypnone. The typical dosage was 0.12 to 0.3 milliliters.[8] It was considered to have superior sedative effects to both paraldehyde and chloral hydrate.[9] In humans, acetophenone is metabolized to benzoic acid, carbonic acid, and acetone.[10]