Acetamide (systematic name: ethanamide) is an

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 CH₃CONH₂. It is an

amide In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a chemical compound, compound with the general formula , where R, R', and R″ represent any group, typically organyl functional group, groups or hydrogen at ...

derived from

ammonia Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...

and

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 compone ...

. It finds some use as a plasticizer 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 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 ...

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

urea Urea, also called carbamide (because it is a diamide of carbonic acid), is an organic compound with chemical formula . This amide has two Amine, amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest am ...

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 (semiotics), sign, or word that indicates, signifies, or is understood as representing an idea, physical object, object, or wikt:relationship, relationship. Symbols allow people to go beyond what is known or seen by cr ...

: Ace.

Production

Laboratory scale

Acetamide can be produced in the laboratory from ammonium acetate by

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 ...

: : 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 ...

of acetylacetone under conditions commonly used in reductive amination. 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. 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 ammonium acetate or via the hydration of

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 class ...

, a byproduct of the production of acrylonitrile: : 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 insul ...

is higher than most organic solvents, allowing it to dissolve

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

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

organic synthesis Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the gen ...

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

Occurrence

Acetamide has been detected near the center of the

Milky Way The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galax ...

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 Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

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

Philae The Philae temple complex (; , , Egyptian: ''p3-jw-rķ' or 'pA-jw-rq''; , ) is an island-based temple complex in the reservoir of the Aswan Low Dam, downstream of the Aswan Dam and Lake Nasser, Egypt. Originally, the temple complex was ...

'' lander on

comet A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

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

s, four of which – acetamide,

, methyl isocyanate, 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 pungent and fruity odour. It is produced on a large scale industrially. Production Propiona ...

– 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.

References

External links

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