Acetophenone is the

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...

C₆H₅C(O)CH₃. It is the simplest aromatic

ketone In organic chemistry, a ketone is an organic compound with the structure , where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (a carbon-oxygen double bond C=O). The simplest ketone is acetone ( ...

. This colorless, viscous liquid is a precursor to useful

resin A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Commo ...

s and fragrances.

Production

Acetophenone is formed as a byproduct of the

cumene process The cumene process (cumene-phenol process, Hock process) is an industrial process for synthesizing phenol and acetone from benzene and propylene. The term stems from cumene (isopropyl benzene), the intermediate material during the process. It ...

, the industrial route for the synthesis of

phenol Phenol (also known as carbolic acid, phenolic acid, or benzenol) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile and can catch fire. The molecule consists of a phenyl group () ...

and

acetone Acetone (2-propanone or dimethyl ketone) is an organic compound with the chemical formula, formula . It is the simplest and smallest ketone (). It is a colorless, highly Volatile organic compound, volatile, and flammable liquid with a charact ...

. In the Hock rearrangement of

isopropylbenzene hydroperoxide Cumene hydroperoxide is the organic compound with the formula C6H5C(CH3)2OOH; this oily liquid is classified as an organic hydroperoxide. Products of decomposition of cumene hydroperoxide are methylstyrene, acetophenone, and 2-phenylpropan-2-o ...

, migration of a methyl group rather than the phenyl group gives acetophenone and methanol as a result of an alternate rearrangement of the intermediate: : The cumene process is conducted on such a large scale that even the small amount of acetophenone by-product can be recovered in commercially useful quantities. Acetophenone is also generated from

ethylbenzene hydroperoxide Ethylbenzene hydroperoxide is the organic compound with the formula C6H5CH(O2H)CH3. A colorless liquid, EBHP is a common hydroperoxide. It has been used as an O-atom donor in organic synthesis. It is chiral. Together with tert-butyl hydroperox ...

. Ethylbenzene hydroperoxide is primarily converted to 1-phenylethanol (α-methylbenzyl alcohol) in the process with a small amount of by-product acetophenone. Acetophenone is recovered or hydrogenated to 1-phenylethanol which is then dehydrated to produce styrene.

Uses

Precursor to resins

Commercially significant

s are produced from treatment of acetophenone with

formaldehyde Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as ...

and a base. The resulting

copolymer In polymer chemistry, a copolymer is a polymer derived from more than one species of monomer. The polymerization of monomers into copolymers is called copolymerization. Copolymers obtained from the copolymerization of two monomer species are som ...

s are conventionally described with the formula , resulting from

aldol condensation An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties (of aldehydes or ketones) react to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), and this is then followed by dehydration t ...

. These substances are components of

coating A coating is a covering that is applied to the surface of an object, or substrate. The purpose of applying the coating may be decorative, functional, or both. Coatings may be applied as liquids, gases or solids e.g. powder coatings. Paints ...

s and

ink Ink is a gel, sol, or solution that contains at least one colorant, such as a dye or pigment, and is used to color a surface to produce an image, text, or design. Ink is used for drawing or writing with a pen, brush, reed pen, or quill. ...

s. Modified acetophenone-formaldehyde resins are produced by the hydrogenation of the aforementioned ketone-containing resins. The resulting

polyol In organic chemistry, a polyol is an organic compound containing multiple hydroxyl groups (). The term "polyol" can have slightly different meanings depending on whether it is used in food science or polymer chemistry. Polyols containing two, th ...

can be further crosslinked with

diisocyanate In organic chemistry, isocyanate is the functional group with the formula . Organic compounds that contain an isocyanate group are referred to as isocyanates. An organic compound with two isocyanate groups is known as a diisocyanate. Diisocyan ...

s. The modified resins are found in coatings, inks and

adhesive Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantage ...

Niche uses

Acetophenone is an ingredient in fragrances that resemble

almond The almond (''Prunus amygdalus'', Synonym (taxonomy)#Botany, syn. ''Prunus dulcis'') is a species of tree from the genus ''Prunus''. Along with the peach, it is classified in the subgenus ''Amygdalus'', distinguished from the other subgenera ...

cherry A cherry is the fruit of many plants of the genus ''Prunus'', and is a fleshy drupe (stone fruit). Commercial cherries are obtained from cultivars of several species, such as the sweet '' Prunus avium'' and the sour '' Prunus cerasus''. The na ...

honeysuckle Honeysuckles are arching shrubs or Vine#Twining vines, twining vines in the genus ''Lonicera'' () of the family Caprifoliaceae. The genus includes 158 species native to northern latitudes in North America, Eurasia, and North Africa. Widely kno ...

jasmine Jasmine (botanical name: ''Jasminum'', pronounced ) is a genus of shrubs and vines in the olive family of Oleaceae. It contains around 200 species native to tropical and warm temperate regions of Eurasia, Africa, and Oceania. Jasmines are wid ...

, and

strawberry The garden strawberry (or simply strawberry; ''Fragaria × ananassa'') is a widely grown Hybrid (biology), hybrid plant cultivated worldwide for its fruit. The genus ''Fragaria'', the strawberries, is in the rose family, Rosaceae. The fruit ...

. It is used in chewing gum. It is also listed as an approved

excipient An excipient is a substance formulated alongside the active ingredient of a medication. They may be used to enhance the active ingredient’s therapeutic properties; to facilitate drug absorption; to reduce viscosity; to enhance solubility; to i ...

by the U.S. FDA.

Laboratory reagent

In instructional laboratories, acetophenone is converted to

styrene Styrene is an organic compound with the chemical formula C6H5CH=CH2. Its structure consists of a vinyl group as substituent on benzene. Styrene is a colorless, oily liquid, although aged samples can appear yellowish. The compound evaporates easi ...

in a two-step process that illustrates the reduction of carbonyls using

sodium borohydride Sodium borohydride, also known as sodium tetrahydridoborate and sodium tetrahydroborate, is an inorganic compound with the formula (sometimes written as ). It is a white crystalline solid, usually encountered as an aqueous basic solution. Sodi ...

and the

dehydration In physiology, dehydration is a lack of total body water that disrupts metabolic processes. It occurs when free water loss exceeds intake, often resulting from excessive sweating, health conditions, or inadequate consumption of water. Mild deh ...

of alcohols: : : A similar two-step process is used industrially, but reduction step is performed by

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to redox, reduce or Saturated ...

over a copper chromite

catalyst Catalysis () is the increase in rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quick ...

: : Being prochiral, acetophenone is also a popular test substrate for asymmetric

experiments.

Drugs

Acetophenone is used for the synthesis of many pharmaceuticals.

Natural occurrence

Acetophenone occurs naturally in many foods including

apple An apple is a round, edible fruit produced by an apple tree (''Malus'' spp.). Fruit trees of the orchard or domestic apple (''Malus domestica''), the most widely grown in the genus, are agriculture, cultivated worldwide. The tree originated ...

cheese Cheese is a type of dairy product produced in a range of flavors, textures, and forms by coagulation of the milk protein casein. It comprises proteins and fat from milk (usually the milk of cows, buffalo, goats or sheep). During prod ...

apricot An apricot (, ) is a fruit, or the tree that bears the fruit, of several species in the genus ''Prunus''. Usually an apricot is from the species '' P. armeniaca'', but the fruits of the other species in ''Prunus'' sect. ''Armeniaca'' are also ...

banana A banana is an elongated, edible fruit – botanically a berry – produced by several kinds of large treelike herbaceous flowering plants in the genus '' Musa''. In some countries, cooking bananas are called plantains, distinguishing the ...

beef Beef is the culinary name for meat from cattle (''Bos taurus''). Beef can be prepared in various ways; Cut of beef, cuts are often used for steak, which can be cooked to varying degrees of doneness, while trimmings are often Ground beef, grou ...

, and

cauliflower Cauliflower is one of several vegetables cultivated from the species '' Brassica oleracea'' in the genus '' Brassica'', which is in the Brassicaceae (or mustard) family. Cauliflower usually grows with one main stem that carries a large, rou ...

. It is also a component of

castoreum Castoreum is a yellowish exudate from the castor sacs of mature beavers used in combination with urine to territorial marking, scent mark their territory. Both beaver sexes have a pair of castor sacs and a pair of anal glands, located in two c ...

, the exudate from the castor sacs of the mature beaver.

Pharmacology

In the late 19th and early 20th centuries, acetophenone was used in medicine. It was marketed as a

hypnotic A hypnotic (from Ancient Greek, Greek ''Hypnos'', sleep), also known as a somnifacient or soporific, and commonly known as sleeping pills, are a class of psychoactive drugs whose primary function is to sleep induction, induce sleep and to trea ...

and

anticonvulsant Anticonvulsants (also known as antiepileptic drugs, antiseizure drugs, or anti-seizure medications (ASM)) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also used in the treatme ...

under brand name Hypnone. The typical dosage was 0.12 to 0.3 milliliters. It was considered to have superior sedative effects to both

paraldehyde Paraldehyde is the cyclic trimer (chemistry), trimer of acetaldehyde molecules. Formally, it is a derivative of 1,3,5-trioxane, with a methyl group substituted for a hydrogen atom at each carbon. The corresponding tetramer is metaldehyde. A colo ...

and

chloral hydrate Chloral hydrate is a geminal diol with the formula . It was first used as a sedative and hypnotic in Germany in the 1870s. Over time it was replaced by safer and more effective alternatives but it remained in use in the United States until at ...

. In humans, acetophenone is metabolized to

benzoic acid Benzoic acid () is a white (or colorless) solid organic compound with the formula , whose structure consists of a benzene ring () with a carboxyl () substituent. The benzoyl group is often abbreviated "Bz" (not to be confused with "Bn," which ...

carbonic acid Carbonic acid is a chemical compound with the chemical formula . The molecule rapidly converts to water and carbon dioxide in the presence of water. However, in the absence of water, it is quite stable at room temperature. The interconversion ...

, and

Hippuric acid Hippuric acid (Greek language, Gr. ''hippos'', horse, ''ouron'', urine) is a carboxylic acid and organic compound. It is found in urine and is formed from the combination of benzoic acid and glycine. Levels of hippuric acid rise with the consumpt ...

occurs as an indirect metabolite and its quantity in urine may be used to confirm acetophenone exposure, although other substances, like toluene, also induce hippuric acid in urine.

Toxicity

The is 815 mg/kg (oral, rats). Acetophenone is currently listed as a Group D

carcinogen A carcinogen () is any agent that promotes the development of cancer. Carcinogens can include synthetic chemicals, naturally occurring substances, physical agents such as ionizing and non-ionizing radiation, and biologic agents such as viruse ...

indicating that there is no evidence at present that it causes cancer in humans.

References

{{Authority control Ketone solvents Excipients GABAA receptor positive allosteric modulators Phenyl compounds Acetyl compounds