Acetamide

Acetamide

Names
Preferred IUPAC name Acetamide
Systematic IUPAC name Ethanamide
Other names Acetic acid amide Acetylamine
Identifiers
CAS Number	60-35-5 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:27856 Y
ChEMBL	ChEMBL16081 Y
ChemSpider	173 Y
DrugBank	DB02736 Y
ECHA InfoCard	100.000.430
EC Number	200-473-5
IUPHAR/BPS	4661
KEGG	C06244 Y
PubChem CID	178
RTECS number	AB4025000
UNII	8XOE1JSO29 Y
CompTox Dashboard (EPA)	DTXSID7020005
InChI InChI=1S/C2H5NO/c1-2(3)4/h1H3,(H2,3,4) Y Key: DLFVBJFMPXGRIB-UHFFFAOYSA-N Y InChI=1/C2H5NO/c1-2(3)4/h1H3,(H2,3,4) Key: DLFVBJFMPXGRIB-UHFFFAOYAC
SMILES O=C(N)C
Properties
Chemical formula	C2H5NO
Molar mass	59.068 g·mol−1
Appearance	colorless, hygroscopic solid
Odor	odorless mouse-like with impurities
Density	1.159 g cm−3
Melting point	79 to 81 °C (174 to 178 °F; 352 to 354 K)
Boiling point	221.2 °C (430.2 °F; 494.3 K) (decomposes)
Solubility in water	2000 g L−1
Solubility	ethanol 500 g L−1 pyridine 166.67 g L−1 soluble in chloroform, glycerol, benzene
log P	−1.26
Vapor pressure	1.3 Pa
Acidity (pKa)	15.1 (25 °C, H2O)
Magnetic susceptibility (χ)	−0.577 × 10−6 cm3 g−1
Refractive index (nD)	1.4274
Viscosity	2.052 cP (91 °C)
Structure
Crystal structure	trigonal
Thermochemistry
Heat capacity (C)	91.3 J·mol−1·K−1
Std molar entropy (S⦵298)	115.0 J·mol−1·K−1
Std enthalpy of formation (ΔfH⦵298)	−317.0 kJ·mol−1
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H351
Precautionary statements	P201, P202, P281, P308+P313, P405, P501
NFPA 704 (fire diamond)	3 1 1
Flash point	126 °C (259 °F; 399 K)
Lethal dose or concentration (LD, LC):
LD50 (median dose)	7000 mg kg−1 (rat, oral)
Safety data sheet (SDS)	External MSDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Acetamide (systematic name: ethanamide) is an organic compound with the formula CH₃CONH₂. It is derived from acetic acid. 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, which has two methyl (CH₃) groups either side of the carbonyl (CO), and urea which has two amide (NH₂) groups in those locations. Acetamide is also a naturally occurring mineral with the IMA symbol: Ace.

Production

Laboratory scale

Acetamide can be produced in the laboratory from ammonium acetate by dehydration:

[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.

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, 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 is higher than most organic solvents, allowing it to dissolve inorganic compounds with solubilities closely analogous to that of water. Acetamide has uses in electrochemistry and the organic synthesis 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 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) 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 – 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

External links

Look up acetamide in Wiktionary, the free dictionary.

• International Chemical Safety Card 0233
• "Acetamide". Webmineral.org.