Acetamide (systematic name: ethanamide) is an

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...

with the formula CH₃CONH₂. It is the simplest

amide In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a compound with the general formula , where R, R', and R″ represent organic groups or hydrogen atoms. The amide group is called a peptide bond when it is ...

derived from

acetic acid Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...

. It finds some use as a

plasticizer A plasticizer ( UK: plasticiser) is a substance that is added to a material to make it softer and more flexible, to increase its plasticity, to decrease its viscosity, and/or to decrease friction during its handling in manufacture. Plasticiz ...

and as an industrial solvent. The related compound ''N'',''N''-dimethylacetamide (DMA) is more widely used, but it is not prepared from acetamide. Acetamide can be considered an intermediate between

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

, which has two methyl (CH₃) groups either side of the carbonyl (CO), and

urea Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid. Urea serves an important r ...

which has two amide (NH₂) groups in those locations. Acetamide is also a naturally occurring mineral with the IMA

symbol A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different conc ...

: Ace.

Production

Laboratory scale

Acetamide can be produced in the laboratory from

ammonium acetate Ammonium acetate, also known as spirit of Mindererus in aqueous solution, is a chemical compound with the formula NH4CH3CO2. It is a white, hygroscopic solid and can be derived from the reaction of ammonia and acetic acid. It is available commerci ...

dehydration In physiology, dehydration is a lack of total body water, with an accompanying disruption of metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental temperature. Mil ...

: : H₄CH₃CO₂] → CH₃C(O)NH₂ + H₂O Alternatively acetamide can be obtained in excellent yield via

ammonolysis In chemistry, ammonolysis (/am·mo·nol·y·sis/) is the process of splitting ammonia into NH2- + H+. Ammonolysis reactions can be conducted with organic compounds to produce amines (molecules containing a nitrogen atom with a lone pair, :N), o ...

acetylacetone Acetylacetone is an organic compound with the chemical formula . It is a colorless liquid, classified as a 1,3-diketone. It exists in equilibrium with a tautomer . These tautomers interconvert so rapidly under most conditions that they are tre ...

under conditions commonly used in

reductive amination Reductive amination (also known as reductive alkylation) is a form of amination that involves the conversion of a carbonyl group to an amine via an intermediate imine. The carbonyl group is most commonly a ketone or an aldehyde. It is considered ...

. It can also be made from anhydrous acetic acid, acetonitrile and very well dried hydrogen chloride gas, using an ice bath, alongside more valuable reagent

acetyl chloride Acetyl chloride (CH3COCl) is an acyl chloride derived from acetic acid. It belongs to the class of organic compounds called acid halides. It is a colorless, corrosive, volatile liquid. Its formula is commonly abbreviated to AcCl. Synthesis On ...

. Yield is typically low (up to 35%), and the acetamide made this way is generated as a salt with HCl.

Industrial scale

In a similar fashion to some laboratory methods, acetamide is produced by

dehydrating In physiology, dehydration is a lack of total body water, with an accompanying disruption of Metabolism, metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental tempe ...

ammonium acetate or via the

hydration Hydration may refer to: * Hydrate, a substance that contains water * Hydration enthalpy, energy released through hydrating a substance * Hydration reaction, a chemical addition reaction where a hydroxyl group and proton are added to a compound * ...

acetonitrile Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile (hydrogen cyanide is a simpler nitrile, but the cyanide anion is not clas ...

, a byproduct of the production of

acrylonitrile Acrylonitrile is an organic compound with the formula and the structure . It is a colorless, volatile liquid although commercial samples can be yellow due to impurities. It has a pungent odor of garlic or onions. In terms of its molecular ...

: : CH₃CN + H₂O → CH₃C(O)NH₂

Uses

Acetamide is used as a plasticizer and an industrial solvent. Molten acetamide is good solvent with a broad range of applicability. Notably, its

dielectric constant The relative permittivity (in older texts, dielectric constant) is the permittivity of a material expressed as a ratio with the electric permittivity of a vacuum. A dielectric is an insulating material, and the dielectric constant of an insulat ...

is higher than most organic solvents, allowing it to dissolve

inorganic compound In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemist ...

s with solubilities closely analogous to that of water. Acetamide has uses in electrochemistry and the

organic synthesis Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one o ...

of pharmaceuticals, pesticides, and antioxidants for plastics. It is a precursor to

thioacetamide Thioacetamide is an organosulfur compound with the chemical formula, formula carbon, C2hydrogen, H5nitrogen, Nsulfur, S. This white crystalline solid is soluble in water and serves as a source of sulfide ions in the synthesis of organic and inorg ...

Occurrence

Acetamide has been detected near the center of the

Milky Way The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye ...

galaxy. This finding is potentially significant because acetamide has an amide bond, similar to the essential bond between amino acids in proteins. This finding lends support to the theory that organic molecules that can lead to life (as we know it on

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

) can form in space. On 30 July 2015, scientists reported that upon the first touchdown of the ''

Philae ; ar, فيلة; cop, ⲡⲓⲗⲁⲕ , alternate_name = , image = File:File, Asuán, Egipto, 2022-04-01, DD 93.jpg , alt = , caption = The temple of Isis from Philae at its current location on Agilkia Island in Lake Nasse ...

'' lander on

comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ar ...

67/P surface, measurements by the COSAC and Ptolemy instruments revealed sixteen

s, four of which – acetamide,

methyl isocyanate Methyl isocyanate (MIC) is an organic compound with the molecular formula CH3NCO. Synonyms are isocyanatomethane and methyl carbylamine. Methyl isocyanate is an intermediate chemical in the production of carbamate pesticides (such as carbaryl, c ...

, and

propionaldehyde Propionaldehyde or propanal is the organic compound with the formula CH3CH2CHO. It is the 3-carbon aldehyde. It is a colourless, flammable liquid with a slightly fruity odour. It is produced on a large scale industrially. Production Propionalde ...

– were seen for the first time on a comet. In addition, acetamide is found infrequently on burning coal dumps, as a mineral of the same name. Acetamide crystal structure

References

External links

* * {{Authority control Hazardous air pollutants IARC Group 2B carcinogens Plasticizers Organic minerals