Acetophenone or methyl phenyl ketone is an aromatic organic compound with the formula C8H8O. It is used in the production of fragrances and resins, as well as a solvent and an intermediate in pharmaceuticals.
| IUPAC Name | 1-phenylethanone |
| Molecular Formula | C8H8O |
| CAS Number | 98-86-2 |
| Synonyms | Methyl phenyl ketone, Phenyl methyl ketone, AP, Acetylbenzene, Benzoyl methyl, Ethyl phenyl ketone, Hypnon |
| InChI | InChI=1S/C8H8O/c1-7(9)8-5-3-2-4-6-8/h2-6H,1H3 |
Acetophenone Structure
The structure of acetophenone consists of a phenyl group bonded to a carbonyl group via a single bond. The carbonyl group is made up of a carbon atom double-bonded to an oxygen atom. The phenyl group is a six-membered ring of carbon atoms with five hydrogen atoms attached, and the sixth position is occupied by the carbonyl carbon atom. This structure gives acetophenone its characteristic properties and allows it to serve as a versatile starting material for the synthesis of a variety of chemicals.
Acetophenone melting point
Acetophenone has a melting point of -15.7 °C. The melting point is the temperature at which a solid changes into a liquid at a constant pressure. Acetophenone is a crystalline solid at room temperature and has a relatively low melting point compared to other similar compounds. The melting point of a compound is determined by its molecular structure and the strength of its intermolecular forces.
Acetophenone IR spectrum
Acetophenone IR spectrum exhibits characteristic peaks at 1705 cm^-1, which corresponds to the carbonyl group, and 3030-3100 cm^-1, which corresponds to the aromatic C-H stretching. These peaks provide important information regarding the functional groups present in the molecule.
Acetophenone molar mass:
Acetophenone has a molar mass of 120.15 g/mol. It is an aromatic organic compound with a carbonyl group attached to a phenyl ring. The molar mass is the sum of the atomic masses of the atoms in one mole of the compound. In the case of acetophenone, it has 8 carbon atoms, 8 hydrogen atoms, and one oxygen atom, which gives a total of 17 atoms in one molecule. The molar mass is an important property of a compound because it is used to calculate the amount of substance in a given sample, which is necessary for various applications in chemistry and industry.
Acetophenone boiling point
Acetophenone has a boiling point of 202 °C. The boiling point is the temperature at which a liquid changes into a gas at a constant pressure. Acetophenone is a volatile organic compound and has a relatively high boiling point compared to other similar compounds. The boiling point of a compound is determined by the strength of its intermolecular forces, which are the forces that hold molecules together in a liquid or solid state. In the case of acetophenone, it has a polar carbonyl group that can form hydrogen bonds with other acetophenone molecules, which makes the intermolecular forces stronger and increases the boiling point.
Methyl phenyl ketone density g/ml
Methyl phenyl ketone has a density of 1.03 g/mL at room temperature. The density is the mass of a substance per unit volume. Methyl phenyl ketone is a liquid at room temperature and has a relatively high density compared to other similar compounds. The density of a compound is determined by its molecular weight and the packing of its molecules in a given volume. In the case of methyl phenyl ketone, it has a relatively high molecular weight and a relatively compact molecular structure, which makes the packing of its molecules more efficient and increases the density.
Methyl phenyl ketone molecular weight
Methyl phenyl ketone has a molecular weight of 120.15 g/mol. The molecular weight is the sum of the atomic weights of all the atoms in a molecule. Methyl phenyl ketone has 8 carbon atoms, 8 hydrogen atoms, and one oxygen atom, which gives a total of 17 atoms in one molecule. The molecular weight is an important property of a compound because it is used to calculate the amount of substance in a given sample, which is necessary for various applications in chemistry and industry.
| Appearance | Colorless to pale yellow liquid |
| Specific Gravity | 1.028-1.031 at 25 °C |
| Color | Colorless to pale yellow |
| Odor | Sweet, floral, honey-like |
| Molar Mass | 120.15 g/mol |
| Density | 1.03 g/mL at 25 °C |
| Melting Point | -15.7 °C |
| Boiling Point | 202 °C |
| Flash Point | 78 °C |
| Water Solubility | 3.3 g/L at 25 °C |
| Solubility | Soluble in alcohol, ether, chloroform, and benzene |
| Vapor Pressure | 0.27 mmHg at 25 °C |
| Vapor Density | 4.15 (air = 1) |
| pKa | 10.01 |
| pH | Not applicable (methyl phenyl ketone is not an acid or base) |
Methyl phenyl ketone Safety and Hazards
Methyl phenyl ketone can be hazardous if not handled properly. It may cause irritation to the skin, eyes, and respiratory system if it comes into contact or is inhaled. Direct exposure to high concentrations of methyl phenyl ketone vapor may cause headaches, dizziness, or nausea. Ingestion of methyl phenyl ketone can cause gastrointestinal irritation, vomiting, or diarrhea. Methyl phenyl ketone is also flammable and may form explosive mixtures with air. It should be stored in a cool, dry, and well-ventilated area away from sources of ignition. Personal protective equipment, such as gloves, safety glasses, and a respirator, should be worn when handling methyl phenyl ketone.
| Hazard Symbols | Xi: Irritant, F: Highly flammable |
| Safety Description | S16: Keep away from sources of ignition – No smoking, S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice, S36: Wear suitable protective clothing, S37: Wear suitable gloves, S39: Wear eye/face protection |
| UN IDs | UN 2319 |
| HS Code | 291439 |
| Hazard Class | 3 (Flammable liquids) |
| Packing Group | III |
| Toxicity | Methyl phenyl ketone is classified as a Category 3 eye irritant and a Category 4 skin irritant. It is not considered to be a carcinogen or mutagen. The oral LD50 (lethal dose for 50% of test subjects) in rats is approximately 3,000 mg/kg. It is not considered to be a significant environmental hazard. |
Methyl phenyl ketone Synthesis Methods
Various methods exist for synthesizing methyl phenyl ketone.
One common method is the Friedel-Crafts acylation of benzene with acetyl chloride in the presence of a Lewis acid catalyst such as aluminum chloride. This reaction produces methyl phenyl ketone and hydrogen chloride as byproducts.
Another method is the oxidation of ethylbenzene using air or oxygen in the presence of a metal catalyst such as cobalt or manganese. This reaction produces methyl phenyl ketone and acetic acid as byproducts.
One can synthesize methyl phenyl ketone by reducing phenylacetone using reducing agents such as sodium borohydride or lithium aluminum hydride. This reaction produces methyl phenyl ketone and the corresponding alcohol as byproducts.
Another method involves the reaction of benzoyl chloride with ethylbenzene in the presence of an aluminum chloride catalyst to produce methyl phenyl ketone and hydrogen chloride as byproducts.
Methyl phenyl ketone Uses
Methyl phenyl ketone has several uses in various industries.
- Methyl phenyl ketone finds widespread use as a solvent for various resins, cellulose esters, and plastics.
- The food industry utilizes methyl phenyl ketone as a flavoring agent, especially for cherry and almond flavors.
- The fragrance industry employs methyl phenyl ketone as a raw material for the production of perfumes and other scented products.
- Various chemicals such as pharmaceuticals, agrochemicals, and dyes are synthesized using methyl phenyl ketone.
- Methyl phenyl ketone serves as an intermediate in the production of phenylacetone, which is a precursor for the synthesis of amphetamines.
- Coumarin, a fragrance used in soaps and detergents, is synthesized from methyl phenyl ketone.
- Organic chemistry reagents utilize methyl phenyl ketone as a reagent for the synthesis of various compounds.
- Methyl phenyl ketone serves as a starting material for the production of other chemicals such as styrene and methyl styrene.
Overall, methyl phenyl ketone has a wide range of applications in various industries due to its versatile properties and uses.
Questions:
Q: Is acetophenone polar?
A: Yes, acetophenone is polar due to the presence of a carbonyl group (C=O) and a phenyl ring, which create a dipole moment.
Q: Is benzaldehyde or acetophenone more polar?
A: Benzaldehyde is more polar than acetophenone because it has a higher dipole moment due to the presence of an aldehyde group (CHO) in addition to the phenyl ring.
Q: Acetophenone IR spectrum?
A: Acetophenone IR spectrum shows a strong and broad absorption band around 1700 cm^-1, which is characteristic of the carbonyl (C=O) stretching vibration. It also shows peaks around 3000-3100 cm^-1, which correspond to the aromatic C-H stretching vibrations.
Q: Acetophenone to benzoic acid?
A: Acetophenone can be converted to benzoic acid by oxidation using an oxidizing agent such as potassium permanganate or chromic acid. This reaction results in the cleavage of the carbon-carbon bond adjacent to the carbonyl group, followed by oxidation of the resulting intermediate to produce benzoic acid.
Q: Benzene to acetophenone?
A: Benzene can be converted to acetophenone by Friedel-Crafts acylation using acetyl chloride or acetic anhydride in the presence of a Lewis acid catalyst such as aluminum chloride. This reaction results in the substitution of one hydrogen atom of benzene with an acetyl group (-COCH3), followed by a rearrangement to form acetophenone.