Acetamide

File:CSD CIF ACEMID06.jpged dimer from X-ray crystallography. Selected distances: C-O: 1.243, C-N, 1.325, N---O, 2.925 Å. Color code: red = O, blue = N, gray = C, white = H.{{cite journal |doi=10.1107/S1600536803019494 |title=A new refinement of the orthorhombic polymorph of acetamide |date=2003 |last1=Bats |first1=Jan W. |last2=Haberecht |first2=Monika C. |last3=Wagner |first3=Matthias |journal=Acta Crystallographica Section E |volume=59 |issue=10 |pages=o1483–o1485 }}]]

Acetamide can be produced in the laboratory from ammonium acetate by dehydration:{{OrgSynth | author1 = Coleman, G. H. | author2 = Alvarado, A. M. | title = Acetamide | volume = 3 | pages = 3 | collvol = 1 | collvolpages = 3 | year = 1923 | prep = cv1p0003 | doi = 10.15227/orgsyn.003.0003}}

: [NH₄][CH₃CO₂] → CH₃C(O)NH₂ + H₂O

Alternatively acetamide can be obtained in excellent yield via ammonolysis of acetylacetone under conditions commonly used in reductive amination.{{cite journal|last1=Schwoegler|first1=Edward J.|last2=Adkins|first2=Homer|author-link2=Homer Burton Adkins|title=Preparation of Certain Amines|journal=J. Am. Chem. Soc.|year=1939|volume=61|issue=12|pages=3499–3502|doi=10.1021/ja01267a081}}

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.

In a similar fashion to some laboratory methods, acetamide is produced by dehydrating ammonium acetate or via the hydration of acetonitrile, a byproduct of the production of acrylonitrile:{{ Ullmann | last1= Cheung |first1=H. |last2=Tanke |first2=R. S. |last3=Torrence |first3=G. P. | title = Acetic Acid | doi = 10.1002/14356007.a01_045.pub2}}

: CH₃CN + H₂O → CH₃C(O)NH₂

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 is higher than most organic solvents, allowing it to dissolve inorganic compounds with solubilities closely analogous to that of water.{{Cite journal|last=Stafford|first=O. F.|date=1933|title=Acetamide as a Solvent|journal=J. Am. Chem. Soc.|volume=55|issue=10|pages=3987–3988|doi=10.1021/ja01337a011}} Acetamide has uses in electrochemistry and the organic synthesis of pharmaceuticals, pesticides, and antioxidants for plastics.{{Cite book|last=Wagner|first=Frank S.|title=Kirk-Othmer Encyclopedia of Chemical Technology|publisher=John Wiley & Sons|year=2002|isbn=9780471238966|doi=10.1002/0471238961.0103052023010714.a02.pub2}} It is a precursor to thioacetamide.{{OrgSynth|author=Schwarz, G.|title=2,4-Dimethylthiazole|volume=25|pages=35|collvol=3|collvolpages=332|year=1945|prep=cv3p0332}}

Acetamide has been detected near the center of the Milky Way galaxy.{{ cite journal |author1=Hollis, J. M. |author2=Lovas, F. J. |author3=Remijan, A. J. |author4=Jewell, P. R. |author5=Ilyushin, V. V. |author6=Kleiner, I. | title = Detection of Acetamide (CH₃CONH₂): The Largest Interstellar Molecule with a Peptide Bond | journal = Astrophys. J. | year = 2006 | volume = 643 | issue = 1 | pages = L25–L28 | doi = 10.1086/505110 | bibcode = 2006ApJ...643L..25H | doi-access = free }} 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) can form in space.

On 30 July 2015, scientists reported that upon the first touchdown of the Philae lander on comet 67/P{{'s}} surface, measurements by the COSAC and Ptolemy instruments revealed sixteen organic compounds, four of which – acetamide, acetone, methyl isocyanate, and propionaldehyde{{cite news |url=https://www.washingtonpost.com/world/philae-probe-finds-evidence-that-comets-can-be-cosmic-labs/2015/07/30/63a2fc0e-36e5-11e5-ab7b-6416d97c73c2_story.html |archive-url=https://web.archive.org/web/20181223235109/https://www.washingtonpost.com/world/philae-probe-finds-evidence-that-comets-can-be-cosmic-labs/2015/07/30/63a2fc0e-36e5-11e5-ab7b-6416d97c73c2_story.html |url-status=dead |archive-date=23 December 2018 |title=Philae probe finds evidence that comets can be cosmic labs |newspaper=The Washington Post |agency=Associated Press |first=Frank |last=Jordans |date=30 July 2015 |access-date=30 July 2015}}{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/Science_on_the_surface_of_a_comet |title=Science on the Surface of a Comet |publisher=European Space Agency |date=30 July 2015 |access-date=30 July 2015}}{{cite journal |last1=Bibring |first1=J.-P. |last2=Taylor |first2=M.G.G.T. |last3=Alexander |first3=C. |last4=Auster |first4=U. |last5=Biele |first5=J. |last6=Finzi |first6=A. Ercoli |last7=Goesmann |first7=F. |last8=Klingehoefer |first8=G. |last9=Kofman |first9=W. |last10=Mottola |first10=S. |last11=Seidenstiker |first11=K.J. |last12=Spohn |first12=T. |last13=Wright |first13=I. |title=Philae's First Days on the Comet - Introduction to Special Issue |date=31 July 2015 |journal=Science |volume=349 |number=6247 |page=493 |doi=10.1126/science.aac5116 |bibcode=2015Sci...349..493B |pmid=26228139|doi-access=free }} – 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.{{ cite web | url = http://www.mindat.org/min-13.html | title = Acetamide | publisher = Mindat.org }}{{ cite web | url = http://rruff.geo.arizona.edu/doclib/hom/acetamide.pdf | title = Acetamide | work = Handbook of Mineralogy | publisher = RRUFF Project }}

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• {{ICSC|0233|02}}
• {{cite web|url=http://www.webmineral.com/data/Acetamide.shtml#.YbXGi73MLIW|title=Acetamide|publisher=Webmineral.org}}

{{Molecules detected in outer space}}

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Category:IARC Group 2B carcinogens

Category:Plasticizers

Category:Organic minerals